Dangane da abubuwan da suka shafi muhalli da canjin makamashi, ragewar CO2 mai amfani da wutar lantarki (ECR) zuwa makamashi da sinadarai masu haɓaka da yawa (C2+), ta amfani da wutar lantarki mai sabuntawa, yana ba da kyakkyawar mafita na dogon lokaci don rufe zagayowar carbon tare da ƙarin fa'idodin tattalin arziƙi.Koyaya, haɗakarwa ta C─C electrocatalytic a cikin ruwa masu ruwa da tsaki har yanzu ƙalubalen buɗaɗɗe ne saboda ƙarancin zaɓi, aiki, da kwanciyar hankali.Zane na masu kara kuzari da reactors suna riƙe da maɓalli don magance waɗannan ƙalubalen.Mun taƙaita ci gaban kwanan nan game da yadda ake samun ingantacciyar hanyar haɗin gwiwar C─C ta hanyar ECR, tare da ba da fifiko kan dabaru a cikin masu amfani da wutar lantarki da ƙirar lantarki/reactor, da hanyoyin da suka dace.Bugu da ƙari, an tattauna ƙulla-ƙulla na yanzu da kuma damar da za a samu don samar da samfurin C2 +.Muna nufin samar da cikakken bita na dabarun haɗin gwiwar C─C na zamani ga al'umma don ci gaba da haɓakawa a cikin mahimman fahimta da aikace-aikacen fasaha.

Yawan sakin carbon dioxide (CO2) cikin yanayi ya haifar da mummunan sakamako na muhalli kuma yana gabatar da barazanar gaggawa kuma mai yuwuwar da ba za a iya jurewa ba ga al'ummomin ɗan adam (1, 2).Yayin da yanayin yanayin CO2 ya karu sosai daga 270 ppm (ɓangarorin da miliyan) a farkon 1800s zuwa 401.3 ppm a cikin Yuli 2015, an cimma yarjejeniya ta duniya kan sake amfani da sawun carbon da ayyukan ɗan adam ke fitarwa (3, 4).Don gane madaidaicin madaidaicin sawun carbon, hanya ɗaya mai yuwuwa ita ce a canza dogaro da makamashi na yanzu da masana'antun sinadarai daga burbushin mai zuwa hanyoyin sabunta su kamar hasken rana da iska (5-8).Koyaya, ɓangarorin makamashi daga waɗannan hanyoyin da ake sabunta su yana iyakance ne kawai zuwa 30% saboda yanayin ɗan lokaci, sai dai idan an sami hanyoyin adana makamashi mai girma (9).Don haka, a matsayin madadin, kama CO2 daga tushen ma'ana kamar tsire-tsire masu wutar lantarki, wanda ke biye da jujjuyawar zuwa kayan abinci da makamashin sinadarai, ya fi dacewa a zahiri (9-12).Ragewar Electrocatalytic CO2 (ECR) ta amfani da wutar lantarki mai sabuntawa yana wakiltar kyakkyawan bayani na dogon lokaci saboda yanayin aiki mai sauƙi da ake buƙata don jujjuyawar, wanda za'a iya samar da samfuran da aka ƙara ƙimar (13).Kamar yadda aka kwatanta a hoto na 1, a cikin wannan tsari, electrochemical electrolyzer yana canza CO2 da ruwa zuwa sinadarai da makamashin wutar lantarki mai sabuntawa.Sakamakon man fetur yana da damar adana dogon lokaci kuma ana iya rarrabawa ko cinyewa, yana ba da CO2 a matsayin babban sharar gida, wanda za a kama shi kuma a mayar da shi zuwa ga reactor don rufe madauki.Haka kuma, ana iya amfani da sakamakon ƙananan ƙwayoyin sinadarai na abinci [misali, carbon monoxide (CO) da formate] daga ECR azaman albarkatun ƙasa don haɗakar sinadarai masu rikitarwa.

Ana iya samun man fetur da sinadarai daga ECR tare da rufaffiyar zagayowar carbon da aka yi amfani da su ta hanyoyin makamashi masu sabuntawa kamar hasken rana, iska, da ruwa.Injiniyan salula da injiniyan haɓakawa suna taka muhimmiyar rawa don haɓaka zaɓi, aiki, da inganci don jujjuyawar CO2 zuwa samfuran C2+ masu ƙima tare da yawan kuzari.

Duk da haka, CO2 ƙwaya ce ta madaidaiciya madaidaiciya tare da ƙaƙƙarfan haɗin C═O (750 kJ mol-1) (14), yana sa ya zama mai wahala ga jujjuyawar electrochemical.Don haka, yana buƙatar babban shingen kunnawa, wanda, bi da bi, yana haifar da manyan abubuwan da suka wuce gona da iri (15).Bugu da ƙari, ECR a cikin electrolyte mai ruwa ya ƙunshi multi-electron/proton canja wurin tafiyar matakai tare da dama daban-daban yiwuwar amsawa tsaka-tsaki da samfurori (16-18), yana sa ya zama mai rikitarwa.Tebu 1 ya taƙaita rabin halayen thermodynamic thermodynamic na manyan samfuran ECR, gami da CO, methane (CH4), methanol (CH3OH), formic acid (HCOOH), ethylene (C2H4), ethanol (CH3CH2OH), da sauransu, tare da su. madaidaicin madaidaicin madaidaicin redox (19).Gabaɗaya, yayin aiwatar da ECR, ƙwayoyin CO2 na farko suna fuskantar adsorption da hulɗa tare da atoms akan farfajiyar mai kara kuzari don samar da * CO2-, sannan canja wuri daban-daban na protons da/ko electrons zuwa samfuran ƙarshe daban-daban.Misali, an yi imanin CH4 yana samuwa ta hanyoyi masu zuwa: CO2 → *COOH → * CO → * CHO → * CH2O → * CH3O → CH4 + * O → CH4 + * OH → CH4 + H2O (20).

Hoto 2A yana taƙaita ƙimar Faradaic (FE) a ƙarƙashin nau'ikan samarwa daban-daban (yawancin halin yanzu) don rahoton ECR electrocatalysts, wanda ke wakiltar zaɓin samfur na amsawa (21-43).Musamman ma, yayin da masu amfani da wutar lantarki na zamani zasu iya canza CO2 zuwa samfurori na C1 (CO ko formate) tare da fiye da 95% FE a karkashin babban adadin samarwa (> 20 mA cm-2 don nau'in nau'in H da> 100 mA cm - 2 don tantanin halitta) (9, 21, 22, 25, 28, 44, 45), zaɓin zaɓi (> 90%) da ingantaccen samar da ƙarin samfuran multicarbon (C2+) sinadarai ba a samu ba ya zuwa yanzu.Wannan shi ne saboda gaskiyar cewa haɗakarwa zuwa samfuran C2+ yana buƙatar isowa da tallata ƙwayoyin CO2 da yawa zuwa saman, canjin matakin mataki, da matsayi na sarari (13).Don zama takamaiman, kamar yadda aka nuna a cikin siffa 2B, halayen da suka biyo baya na * CO masu tsaka-tsaki sun ƙayyade samfuran C2 + na ƙarshe na ECR.Gabaɗaya, C2H6 da CH3COO- suna raba * CH2 matsakaici, wanda aka samo shi daga matakan canja wurin lantarki mai haɗakar da proton na * CO.Ƙarin protonation na * CH2 yana ba da * CH3 matsakaici, wanda ke haifar da samuwar C2H6 ta hanyar * CH3 dimerization.Ba kamar ƙarni na C2H6 ba, CH3COO- an kafa ta ta hanyar shigar da CO cikin * CH2.Matsakaicin * CO shine matakin tantance ƙimar C2H4, CH3CH2OH, da n-propanol (n-C3H7OH).Bayan jerin matakan canja wurin lantarki da matakan protonation, * CO─CO dimer ya samar da matsakaicin * CH2CHO, wanda ke aiki azaman matakin tantance zaɓi don C2H4 da C2H5OH.Bugu da ƙari, an gano cewa rage * CH2CHO zuwa C2H4 yana da ƙananan shingen makamashi fiye da canza * CH3CHO zuwa C2H5OH (46), wanda zai iya bayyana mafi girma FE don C2H4 akan C2H5OH akan yawancin abubuwan jan karfe.Bugu da ƙari, tsayayyen matsakaitan C2 na iya canzawa zuwa n-C3H7OH ta hanyar shigar da CO.Hanyoyi masu hadaddun da ba za a iya sarrafa su ba yayin samar da sinadarai na C2+ galibi saboda ƙarin haɓakawa da yawa zuwa rukunin protonation, tare da yuwuwar shigar da matakan da ba na lantarki ba (19, 47).Don haka, ƙira na zaɓaɓɓen electrocatalysts shine abin da ake buƙata don takamaiman samfurin C2+ a babban yawan amfanin ƙasa.A cikin wannan bita, muna nufin haskaka ci gaban da aka samu a kwanan nan akan dabaru a ƙirar lantarki don zaɓin samfuran C2+ ta hanyar ECR.Muna kuma bayar da taƙaitaccen fahimtar hanyoyin da ke da alaƙa.Hakanan za'a nanata ƙirar Electrode da reactor don nuna yadda ake samun ingantaccen aiki, kwanciyar hankali, da babban aiki na ECR.Bugu da ƙari, za mu tattauna sauran ƙalubalen da dama na gaba don canza sinadarin lantarki na CO2 zuwa sinadarai masu ƙara darajar C2+.

(A) FE a ƙarƙashin nau'o'in samarwa daban-daban (yawan halin yanzu) don rahoton ECR electrocatalysts (21-43, 130).(B) Mafi yuwuwar hanyoyin C2+ yayin ECR.An sake bugawa tare da izini daga Ƙungiyar Kiwon Lafiya ta Amirka (47).

Canjin Electrocatalytic na CO2 zuwa makamashin sinadarai da kayan abinci shine yuwuwar fasaha don cimma zagayen makamashi na tsaka tsaki na carbon (11).Koyaya, FE na samfuran C2 + har yanzu yana da nisa daga aikace-aikacen da ake amfani da su, inda masu haɓaka fasahar zamani ke ba da damar samar da samfuran C2 tare da kusan 60% FE (13, 33), yayin da samar da C3 ke iyakance ga ƙasa da 10% FE (48, 49).Rage haɗe-haɗe na CO2 zuwa samfuran C2+ yana buƙatar masu haɓakawa iri-iri tare da ingantaccen tsarin halittar jiki da kaddarorin lantarki (50, 51).Fuskar mai kara kuzari yana buƙatar karya alaƙar sikeli tsakanin masu tsaka-tsaki (47, 52, 53).Haka kuma, don cimma nasarar samuwar haɗin C─C, tsaka-tsakin amsawar da aka sha a saman mai kara kuzari dole ne ya kasance kusa da juna.Bugu da ƙari, hanyar daga farkon da aka tallata tsaka-tsaki zuwa takamaiman samfurin C2+ yana buƙatar sarrafa shi da kyau saboda matakan canja wurin lantarki da yawa na taimakon proton.Idan akai la'akari da babban hadaddun rage CO2 zuwa samfuran C2+, ya kamata a keɓance masu amfani da wutar lantarki a hankali don ƙara zaɓin zaɓi.Dangane da matsakaicin nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau’in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau‘in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau’in nau'in nau'in nau'in nau’in nau’in nau’in nau’in nau’in nau’in nau’in nau’in nau’in halitta), mun rarraba samfuran C2+ zuwa manyan abubuwan hydrocarbons da oxygenates (4, 54).Don kusanci ingantacciyar ingantattun na'urorin lantarki don ƙayyadaddun ƙwayoyin kwayoyin C2 +, dabarun ƙira da yawa masu haɓakawa, kamar heteroatom doping, tsarin tsarin crystal, gami / dillalai, daidaita yanayin yanayin iskar shaka, da sarrafa ligand, an nuna su (35, 41, 55-61) .Mafi kyawun ƙira yakamata yayi la'akari da abubuwan da aka ambata a hankali kuma ya haɓaka fa'idodi.In ba haka ba, fahimtar abin da dalilai masu aiki na rukunin yanar gizo ke haifar da irin wannan keɓantaccen ɗabi'a na motsa jiki na iya ƙara haskaka madaidaicin ƙira don haɗakarwar C─C.Don haka, yadda za a ƙirƙira mai haɓaka ECR zuwa takamaiman samfuran (multicarbon hydrocarbons da oxygenates) da tsarin da ke da alaƙa za a tattauna a wannan ɓangaren.

C2+ hydrocarbons, irin su C2H4, sune sunadarai nexus don masana'antun sinadarai iri-iri, kamar samar da polyethylene (62, 63).Bayan haka, ana iya amfani da shi kai tsaye azaman mai don walda ko wani abu mai gauraye a cikin iskar gas (12).An yi amfani da hydrogenation na CO (Fischer-Tropsch synthesis) da CO2 don samar da C2 + hydrocarbons na dogon lokaci a cikin ma'auni na masana'antu amma an kalubalanci amfani da makamashi mai yawa da tasirin muhalli (64).Sabanin madaidaicin, ragewar CO2 na electrochemical ta amfani da makamashi mai sabuntawa yana samar da mafi tsabta kuma mafi dorewa hanya.An yi babban ƙoƙari don haɓaka ingantattun na'urorin lantarki zuwa C2+ hydrocarbons (32, 33, 65-70).

An bincika masu amfani da wutar lantarki na Bimetallic don karya alaƙar haɓakawa yayin juyawar CO2 na electrochemical, wanda zai iya daidaita tsaka-tsakin maɓalli kuma ya rage ƙarfin ƙarfi kuma, ta haka, bi da bi, ƙara zaɓin (71-74).Yayin da jerin kayan gami da suka haɗa da Au-Cu, Ag-Cu, Au-Pd, da Cu-Pt an nuna su don ingantaccen samar da C1 ta hanyar tabbatar da tsaka-tsaki mai mahimmanci (73, 75), tasirin gami ga haɓakar C2+ hydrocarbon alama. ya zama mafi hadaddun (76).Misali, a cikin tsarin bimetallic Cu-Ag, ana iya sarrafa rarraba samfuran cikin sauƙin sarrafawa ta hanyar daidaita yanayin atomic na saman Ag da Cu (77).The surface Cu-arzikin samfurin ne fĩfĩta ga hydrocarbon samar, yayin da kayayyakin na surface Ag-arzikin daya mamaye CO, nuna muhimmancin atomic rabo ga alloyed ECR electrocatalysts.Tasirin geometric da tsarin atomic na gida ya haifar zai iya tasiri sosai ga ƙarfin ɗaure na tsaka-tsaki.Gewirth da abokan aiki (36) sun nuna cewa Cu-Ag alloys daga ƙari-sarrafa electrodeposition nuna ~ 60% FE ga C2H4 a cikin wani alkaline kwarara electrolyzer (Fig. 3, A da B).A wannan yanayin, ana iya samun ingantaccen zaɓi na C2H4 ta hanyar ilimin halittar jiki da daidaitawar Ag-loading.An yi imanin rukunin yanar gizon Ag suna taka rawar mai talla don ƙirƙirar CO yayin ECR.Sa'an nan, mafi kyawun samuwa na tsaka-tsakin CO na iya taimakawa haɗin C─C a cikin maƙwabtan Cu.Bayan haka, Ag kuma na iya haɓaka samuwar Cu2O a lokacin haɓakar haɓakar Cu-Ag (Fig. 3C), wanda ke haifar da ingantaccen samar da C2H4.Wannan haɗin gwiwa yana buɗe sabbin dama don haɓaka abubuwan haɗakarwa na C─C.Bugu da ƙari, tsarin haɗakar ƙarfe daban-daban a cikin tsarin gami na iya ƙayyade rarraba samfuran ECR.Yin amfani da Pd-Cu alloy a matsayin misali (Fig. 3D), Kenis da abokan aiki (71) sun nuna cewa Pd-Cu mai haɓakawa na zamani zai iya ba da zaɓi mafi girma (~ 50%) don C2H4 idan aka kwatanta da umarninsa da rashin daidaituwa. takwarorinsu.Bisa ga ka'idar d-band, yawanci, ƙarfen miƙa mulki tare da ƙananan cibiyar d-band yana nuna raunin daurin tsaka-tsakin da aka samar a kan filayen ƙarfe (78).Yayinda Pd-Cu alloy mai raba lokaci ya baje kolin irin wannan zaɓi na katalytic da ayyuka don CO tare da Cu nanoparticles (NPs), yana ba da ƙarfin ɗauri daban-daban zuwa tsaka-tsaki ta hanyar kunna Pd.Kamar yadda aka nuna a cikin siffa 3E, Cu-Pd alloy wanda aka raba lokaci-lokaci ya nuna cibiyar d-band mafi ƙasƙanci, yayin da na Cu NP shine mafi girma.Yana ba da shawarar cewa alloy na Cu-Pd na zamani yana da mafi ƙarancin ƙarfin ɗaure don matsakaicin CO.Wannan abin lura yana nuna cewa tasirin geometric da tsarin zai iya taka rawar gani fiye da tasirin lantarki don haɓaka zaɓin zaɓi na hydrocarbon a cikin keɓancewar alloy na Cu-Pd.Ya zuwa yau, kawai jan ƙarfe mai tsaftataccen ƙarfe ko ƙarfe na tushen jan ƙarfe yana nuna zaɓi mafi girma da aiki don rage yawan sinadarai na CO2 zuwa C2+ hydrocarbons.Don haka, yana da matukar mahimmanci don haɓaka novel electrocatalyst don samar da C2+ hydrocarbon daga ECR.Ƙaddamar da CO2 hydrogenation, wani bincike na farko ya nuna cewa Ni-Ga alloy tare da matakai daban-daban za a iya amfani da su don tsarawar C2H4 (79).Ya nuna cewa fim din Ni5Ga3 zai iya rage CO2 zuwa C2H4 da ethane (C2H6).Kodayake FE zuwa C2+ hydrocarbons bai wuce 5% ba, yana iya buɗe sabbin layin don gwajin lantarki zuwa haɗin C─C dangane da tasirin gami.

(A zuwa C) Cu-Ag bimetallic catalysts ƙirƙira ta ƙara-sarrafa electrodeposition: (A) scanning electron microscopy (SEM) na Cu waya, Cu-Ag poly, da Cu-Ag waya da (B) m C2H4 FE.(C) EXAFS ya nuna cewa Cu-Ag waya an haɗa shi tare kuma an gabatar da Cu (I) oxide.(A) zuwa (C) ana sake bugawa tare da izini daga American Chemical Society (36).(D da E) Cu-Pd masu haɓakawa tare da nau'ikan hadawa daban-daban: (D) Hoto, hotuna na watsawa na lantarki (TEM), da taswirar abubuwa masu tarwatsa makamashi na odar, rashin ƙarfi, da rabe-raben Cu-Pd gami da (E) ) surface valence band photoemission spectra da d-band cibiyar (layin tsaye) na Cu-Pd gami da matakin Fermi.(D) da (E) ana sake yin su tare da izini daga Societyungiyar Kemikal ta Amurka (71).au, raka'a na sabani.

Bayan tasirin alloy, sarrafa jihohin iskar shaka wata babbar ka'ida ce don daidaita ayyukan lantarki, wanda zai iya shafar tsarin lantarki na gida na kayan.Misali na farko don daidaita yanayin oxidation na mai kara kuzari shine amfani da kayan da aka samu oxide.Ragowar nau'in iskar oxygen a saman ko ƙasa na mai kara kuzari bayan raguwa a cikin wurin zai iya daidaita yanayin oxidation na cibiyar ƙarfe.Misali, Plasma-oxidized Cu ya nuna fiye da 60% zaɓin zuwa C2H4, wanda aka danganta ga Cu + (37).Don tabbatar da cewa Cu + shine maɓallin maɓalli don babban zaɓi na ethylene, mun yi gwaje-gwajen sarrafawa ta amfani da plasma daban-daban (Fig. 4A).A situ hard x-ray absorption spectroscopy ya kara nuna cewa ragowar oxides a cikin (sub) saman Layer sun tsaya tsayin daka akan yanayin ragewa, tare da adadi mai yawa na nau'in Cu+ da suka rage bayan sa'a 1 na raguwa a ingantacciyar ma'auni na -1.2 V tare da mai canzawa. hydrogen Electrode (RHE).Bugu da ƙari kuma, electrodeposition na jan karfe daga sol-gel jan karfe oxychloride sake tabbatar da cewa stabilized surface Cu + jinsin iya inganta selectivity na C2H4 (61).An bin diddigin yanayin iskar oxygen ta mai kara kuzarin jan ƙarfe a ƙarƙashin maɓalli daban-daban da aka yi amfani da su ta hanyar amfani da lokaci mai warwarewa a cikin yanayin yanayin shayar da radiyo mai laushi.Matakin sauyawa na farko daga Cu2+ zuwa Cu+ yana da sauri sosai;duk da haka, ƙarin rage yawan nau'in nau'in Cu+ zuwa Cu0 yana da hankali sosai.Kusan kashi 23% na nau'in Cu+ sun kasance ko da bayan raguwar sa'o'i 1 a ƙarƙashin -1.2 V da RHE (Fig. 4B).Nazarin injiniya ya nuna cewa mu'amala tsakanin Cu+ da Cu0 yana haifar da jan hankali na electrostatic tsakanin masu tsaka-tsaki tun lokacin da C atom na * CO@Cu+ yana da cajin gaskiya, yayin da na * CO@Cu0 ana cajin mara kyau (80), wanda, bi da bi, yana haɓaka C─C bond samuwar kuma ta haka yana samar da C2+ hydrocarbons.Baya ga kayan da aka samu oxide, an kuma yi amfani da nitride na jan karfe (Cu3N) don cimma (sub) nau'in saman Cu+ don rage shingen makamashi na * CO (81).Bugu da kari, idan aka kwatanta da Cu da aka samu oxide, nau'in Cu+ da aka samu daga Cu3N sun ma fi kwanciyar hankali (Fig. 4C).A sakamakon haka, mai samar da jan ƙarfe na nitride yana nuna FE na 39 ± 2% don C2H4, wanda ya fi dacewa da Cu (~ 23%) da Cu (~ 28%) oxide.Daidai da tsarin da aka ambata na Cu+/C, an yi amfani da boron azaman dopant heteroatom don gabatarwa da daidaita Cuδ+ (41).Ana iya sarrafa matsakaicin yanayin iskar oxygenation na jan karfe daga +0.25 zuwa +0.78 ta hanyar canza maida hankali na boron dopant.Ƙirar da aka yi hasashe na jihohi ya nuna cewa electrons ɗin ana canjawa wuri daga jan ƙarfe zuwa boron, wanda ke haifar da dopant-induced tabbataccen cajin wuraren tagulla.Boron-doped jan ƙarfe ya nuna ƙarar samar da makamashi na *CHO matsakaici kuma, don haka, ya danne hanyar amsawa zuwa samfuran C1.Bugu da kari, yana iya ƙara zaɓin zuwa multicarbon hydrocarbons ta rage * CO dimerization dauki makamashi (Fig. 4D).Ta hanyar haɓaka matsakaicin yanayin iskar oxygenation na jan karfe, babban C2 FE na ~ 80% tare da ~ 53% C2H4 za a iya samu a ƙarƙashin matsakaicin yanayin iskar oxygenation na jan karfe na +0.35 (Fig. 4E).Har zuwa yau, an gano wuraren da ke aiki akan jan karfe a matsayin Cu0, Cuδ+, da/ko keɓantawar su don ECR a cikin karatu daban-daban (39, 41, 42, 81, 82).Koyaya, menene rukunin yanar gizon da ke aiki har yanzu ana muhawara.Yayin da heteroatom doping-induced Cuδ+ masu kara kuzari an nuna cewa suna aiki sosai ga ECR zuwa samfuran C2+, tasirin haɗin gwiwa daga lahani da aka haifar a lokaci guda kuma ya kamata a yi la'akari da su.Don haka, ya kamata a haɓaka tsarin tsarin operando don gano cibiyar da ke kan saman jan karfe da kuma lura da yuwuwar canjin wurin wuraren aiki a ƙarƙashin yanayin halayen.Bayan haka, kwanciyar hankali na jan karfe mai inganci wani abin damuwa ne a ƙarƙashin yanayin raguwar sinadaran lantarki.Yadda ake haɗa masu kara kuzari tare da tsayayyun rukunin yanar gizo na Cuδ+ ya kasance ƙalubale.

(A) Takaitaccen zaɓin zaɓin C2H4 na nau'ikan jan ƙarfe da ke kunna plasma daban-daban.An sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (37).Sikelin sanduna, 500 nm.(B) Ratio na Cu oxidation jihohin dangane da lokacin amsawa a -1.2 V da RHE a cikin jan ƙarfe na lantarki.An sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (61).(C) Ratio na nau'in Cu + tare da aikin lokacin amsawa a -0.95 V da RHE a cikin Cu-on-Cu3N ko Cu-on-Cu2O.An sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (81).(D) Boron doping ya sami damar canza matsakaicin ƙarfin adsorption na CO a cikin saman jan ƙarfe kuma ya rage ƙarfin kuzarin dimerization CO─CO.1 [B], 2 [B], 3 [B], 4 [B], da 8 [B] suna nuni ne ga yawan abubuwan da ake amfani da su na boron doping a cikin abubuwan jan ƙarfe, waɗanda sune 1/16, 1/8, 3/ 16, 1/4, da 1/2, bi da bi.(E) Dangantakar da ke tsakanin yanayin oxidation da FE na samfuran C2 ko C1 a cikin abubuwan jan ƙarfe na boron-doped.(D) da (E) ana sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (41).(F) Hotunan SEM na foils na jan karfe tare da kauri daban-daban na fina-finan Cu2O kafin (saman) da bayan (kasa) ECR.An sake bugawa tare da izini daga Ƙungiyar Kimiyya ta Amirka (83).

Baya ga tsarin lantarki, abubuwan da aka samo daga oxide kuma na iya haifar da ilimin halittar jiki ko tsarin juyin halitta yayin aiwatar da rage yanayin.Daga hangen nesa na ilimin halittar jiki ko tsari, ingantaccen aikin electrochemical na oxide-samu electrocatalysts an danganta shi da samuwar iyakoki mai aiki, gefuna, da matakai (83-85).Yeo da abokan aiki (83) sun ba da rahoton zaɓaɓɓen C─C haɗakarwa akan fina-finai na Cu2O masu kauri da kauri daban-daban (Fig. 4F).A wurin Raman spectroscopy ya bayyana cewa an rage saman fina-finan Cu2O zuwa karfaffen Cu0 yayin ECR (83).Sakamakon haka, an tabbatar da Cu0 mai ƙarfe a matsayin cibiyar aiki mai ƙarfi maimakon nau'in Cu+ ko ƙirar Cu+/Cu0.A cikin aiwatar da rage Cu2O zuwa karfen Cu0, mai yuwuwa saman mai kara kuzari ya zama matakai, gefuna, da filaye.An nuna cewa matakan da aka kafa da gefuna sun fi aiki fiye da terraces, sun samo asali ne daga ƙarfin daurin su tare da * CO, wanda zai iya ƙara hydrogenate * CO zuwa * CHO ko * CH2O.Bayan haka, gefuna Cu atom masu tallata ne don haɓaka * CHO da * samuwar CH2O.Ayyukan da suka gabata sun ba da shawarar cewa * CHO da * CH2O matsakaici sun fi dacewa don haɗin gwiwar C─C fiye da * CO a cikin motsi (86).Ta hanyar daidaita yanayin halittar jiki, ana iya inganta ƙarfin chemisorption na * CHO da * CH2O matsakaici.A cikin wannan binciken, mawallafa sun gano cewa FE na C2H4 ya ragu daga 40 zuwa 22% lokacin da suka kara yawan kauri na fim din Cu2O daga 0.9 zuwa 8.8 μm.Wannan ya faru ne saboda ƙaddamar da ƙananan haɗin Cu wanda ya karu tare da karuwa a cikin kauri na Cu2O.Waɗannan atom ɗin da ba a haɗa su ba suna iya ɗaure da ƙarfi da H kuma, don haka, an fi fifita don juyin halittar hydrogen fiye da haɗakar C─C.Wannan aikin ya nuna cewa mai kara kuzarin jan ƙarfe na oxide na iya haɓaka zaɓin C2H4 ta hanyar sake gina yanayin halittar jiki maimakon gabatar da nau'in Cuδ+ da aka caje.Yin amfani da abubuwan da aka samu oxide, ethane (C2H6) shima an zaɓi shi da taimakon palladium (II) chloride (PdCl2) ƙari a cikin electrolyte (34).Ya nuna cewa PdClx da aka tallata akan saman Cu2O-derived Cu ya taka muhimmiyar rawa ga juyin halittar C2H6.Musamman, CO2 an fara ragewa zuwa C2H4 a wuraren Cu2O da aka samu masu aiki, sannan za a samar da C2H4 da aka kafa tare da taimakon PdClx da aka tallata don samar da C2H6.FE na C2H6 ya karu daga <1 zuwa 30.1% tare da taimakon PdCl2.Wannan aikin yana ba da shawarar cewa haɗuwa da ingantaccen ma'anar ECR mai haɓakawa da ƙari na electrolyte na iya buɗe sabbin dama don ƙayyadaddun samfuran samfuran C2 +.

Ilimin ilimin halittar jiki da/ko tsarin tsarin yana wakiltar wata madadin dabara don daidaita zaɓin zaɓi da aiki.Sarrafa girman, siffa, da fallasa fuskokin masu haɓakawa an nuna su sosai don haɓaka aikin ECR (58, 87, 88).Misali, Fuskar Cu (100) an fi son intrinsically don tsarar C2H4, yayin da mafi rinjayen samfur daga Cu (111) mai kara kuzari shine methane (CH4) (87).A cikin nazarin Cu nanocrystals tare da nau'i daban-daban da masu girma dabam, Buonsanti da abokan aiki (58) sun bayyana girman girman girman girman girman C2H4 a cikin nanocrystals mai siffar cube (Fig. 5A).A zahiri, cubic Cu nanocrystals sun baje kolin ayyukan C2H4 mafi girma da zaɓin zaɓi fiye da yanayin Cu nanocrystals saboda fifikon fuskar (100).Karamin girman kristal na cubic Cu zai iya ba da ayyuka mafi girma saboda ƙara yawan tattarawar wuraren da ba a daidaita su ba, kamar sasanninta, matakai, da kinks.Koyaya, mafi ƙarfi chemisorption na ƙananan rukunin yanar gizo yana tare da mafi girma H2 da zaɓin CO, wanda ya haifar da ƙarancin ƙarancin hydrocarbon FE.A daya hannun, rabo daga gefen gefen shafukan zuwa jirgin sama ya ragu tare da karuwa a cikin girma masu girma dabam, wanda kuma yana rinjayar aikin samar da C2H4.Marubutan sun nuna cewa matsakaicin girman nanocubes na jan karfe tare da tsayin gefen 44-nm sun nuna mafi girman zaɓi na C2H4 saboda ingantacciyar ma'auni tsakanin girman barbashi da yawa na rukunin yanar gizo.Bugu da ƙari kuma, ilimin halittar jiki yana iya rinjayar pH na gida da kuma jigilar jama'a yayin ECR.An nuna cewa babban pH na gida a cikin kusancin sararin samaniya, wanda aka haifar da shi ta wurin samar da OH-, yana hana hanyar amsawar proton.Sakamakon haka, za a iya haɓaka samuwar C2+ ta hanyar * CO dimerization, kuma ana iya hana CH4 ta hanyar * matsakaicin COH.An nuna tsararrun nanowire na jan karfe (Fig. 5B) don cimma karuwar pH na gida (68).A matsayin electrolyte da aka saba amfani da shi, CO2 cikakken bayani na potassium bicarbonate (KHCO3) zai kawar da OH- (HCO3- + OH- = CO32- + H2O) da sauri kuma ya rage pH na gida.Tare da ƙayyadaddun microstructure, watsawar HCO3- cikin tsararrun Cu nanowire za a iya raunana ta ko ta yaya ta yadda za a danne tasirin neutralization na OH- na gida zuwa wani mataki.Dangane da irin wannan ka'ida, tagulla meshes tare da mesopores masu sarrafawa daidai (Fig. 5C) sun nuna ingantaccen FE don samar da C2H4 ko C2H6 (32).Ya nuna cewa pH na gida a cikin farfajiyar lantarki za a iya ƙarawa ta hanyar rage nisa na pore, wanda ya haifar da ragewar C1 samfurin FE da haɓaka samfurin C2 FE.Bayan haka, ta hanyar haɓaka zurfin rami, ana iya kunna babban samfurin ragewa daga C2H4 zuwa C2H6.FE na C2H6 ya kai 46%.Tun da an kulle sinadarai a cikin pores a lokacin ECR, an bayyana tsawon lokacin riƙewa na maɓalli masu zurfi da ke haifar da zurfafan pores a matsayin babban dalilin babban zaɓi ga cikakken C2 hydrocarbon.Cu nanofibers da aka samo daga CuI kuma ya nuna babban zaɓi zuwa C2H6 (FE = 30% a -0.735 V da RHE) (89).Halin ilimin halittar jiki na anisotropic da girman girman saman Cu nanofibers da aka samo daga CuI zai iya inganta ingantaccen tarko na ɗaukar H2 kuma don haka ƙara FE na C2H6.

(A zuwa C) Ilimin halittar jiki ko tasirin tsari.(A) Yawan zarra (axis na hagu) da rabon atom a gefen gefen (Ndge) zuwa atoms akan jirgin (100) (N100) (axis dama) dangane da tsayin gefen (d).An sake bugawa tare da izini daga John Wiley da Sons (58).(B) Tsarin ilimin halittar jiki ya haifar da canjin pH.An sake bugawa tare da izini daga John Wiley da Sons (68).(C) Zaɓin samfur na mesopore jan ƙarfe tare da girman pore daban-daban da zurfin zurfi.An sake bugawa tare da izini daga John Wiley da Sons (32).(D zuwa H) tasirin Ligand.(D da E) ECR akan jan karfe nanowire (Cu NW) tare da nau'ikan amino acid (D) ko masu gyara (E) a -1.9 V. An sake bugawa tare da izini daga Royal Society of Chemistry (35).(F) Yawan samarwa na C2H4 a cikin daban-daban halide electrolytes tare da daban-daban adsorption yuwuwar akan Cu (35).An sake bugawa tare da izini daga Ƙungiyar Kimiyya ta Amirka (91).NHE, al'ada hydrogen electrode.(G) FE na C2H4 da CO a cikin nau'i-nau'i daban-daban na KOH electrolytes da (H) Tafel gangaren C2H4 a cikin nau'i daban-daban na KOH electrolytes.(G) da (H) an sake bugawa daga Ƙungiyar Amirka don Ci gaban Kimiyya (AAAS) (33).

Gyaran yanayi mai haɓakawa ta amfani da ƙananan ƙwayoyin cuta wani sanannen dabarun inganta aikin lantarki na ECR.Wannan dabarar na iya rinjayar microenvironment kusa da farfajiyar mai haɓakawa, wanda zai iya daidaita maɓalli masu mahimmanci saboda hulɗar tsakanin ligand da tsaka-tsaki.An ba da rahoton Amine azaman mai gyara don haɓaka ECR (35).Amino acid daban-daban, ciki har da glycine (Gly), dl-alanine (Ala), dl-leucine (Leu), dl-tryptophan (Tyr), dl-arginine (Arg), da dl-tryptophan (Trp), an bincika su nazarin tasirin su akan nanowires na jan karfe (35).Kamar yadda aka nuna a cikin siffa 5D, duk ligands na tushen amino acid sun sami damar inganta zaɓin C2+ hydrocarbons.Irin wannan haɓakawa yana nuna cewa ─COOH da ─NH2 ƙungiyoyin aiki a cikin amino acid mai yiwuwa ne ke da alhakin ingantaccen zaɓi na ECR.Rahotannin da suka gabata sun nuna cewa an sami nasarar shigar da amino acid a saman Cu ta duka ƙungiyoyin ─COOH da ─NH2 (35, 90).Stearic acid (C17H35COOH, RCO2H), wanda ya ƙunshi ƙungiyar ─COOH kawai, an zaɓi don gano rawar ─COOH.Sauran masu gyara, irin su a-anthraquinone diazonium gishiri (AQ), o-nitrobenzene diazonium gishiri (PhNO2), da dodecyl mercaptan (C12H25SH, RSH), wanda ba ya ƙunshi ─COOH ko ─NH2 ƙungiyoyi, an kuma bincika.Duk da haka, dukansu ba su da kyau ga C2 + hydrocarbon FE ingantawa (Fig. 5E).Ƙididdigar ƙididdiga ta nuna cewa ─NH3+ ƙungiyoyi a cikin adsorbed zwitterionic glycine na iya daidaitawa * CHO matsakaici saboda ƙaƙƙarfan hulɗar su, irin su hydrogen bonds.Gabatarwar ions halide a cikin electrolyte wata hanya ce ta gyara masu kara kuzari (91, 92).Kamar yadda aka nuna a cikin siffa 5F, ƙimar samar da C2H4 akan plasma-kunna Cu za a iya ƙarawa sosai tare da taimakon abubuwan ƙari na halide.An nuna cewa I-ion ya fi aiki fiye da Br- da Cl-, a cikin yarjejeniya tare da madaidaicin ƙarfin tallan I-, Br-, da Cl- akan Cu (100) facet (91).Bayan halides, hydroxide ion kuma ya nuna tasiri mai kyau akan zaɓin C2H4.Kwanan nan, Sargent da abokan aiki (33) sun ba da rahoton canjin CO2-to-C2H4 tare da ~ 70% FE ta amfani da potassium hydroxide (KOH) electrolyte mai mahimmanci (har zuwa 10 M) a cikin tantanin halitta.Kamar yadda aka nuna a cikin siffa 5G, yuwuwar farawa na CO da C2H4 a cikin 10 M KOH electrolyte ya kasance ƙasa da ƙasa idan aka kwatanta da na 1 M KOH.Bugu da ƙari kuma, gangaren Tafel (Fig. 5H) na haɓakar C2H4 ya ragu tare da haɓakar haɓakar hydroxide (135 mV shekaru goma-1 a cikin 1 M KOH da 65 mV shekaru goma-1 a cikin 10 M KOH), yana ba da shawarar canzawar ƙimar gabaɗaya- kayyade mataki.Sakamakon ka'idar aiki mai yawa (DFT) ya tabbatar da cewa kasancewar tattarawar hydroxides na iya rage ƙarfin dauri na tsaka-tsakin CO sannan kuma yana ƙara rashin daidaituwa tsakanin ƙwayoyin carbon guda biyu a cikin tsaka-tsakin OCCO.Sakamakon haka, matsakaicin OCCO zai ƙara daidaitawa ta hanyar jan hankali na dipole mai ƙarfi, wanda zai haifar da raguwar shingen makamashi na kunnawa don dimerization CO, wanda hakan zai inganta aikin gabaɗaya.

C2+ oxygenates kamar ethanol (CH3CH2OH) wani babban nau'i ne na samfuran ECR masu mahimmanci.Haɗin masana'antu na ethanol tsari ne mai ƙarfi mai ƙarfi, wanda kuma yana cinye babban adadin ethylene ko kayan abinci na noma (40).Don haka, samar da electrocatalytic na ethanol ko wasu C2 + oxygenates daga CO2 yana da ma'anar tattalin arziki da muhalli mai yawa.Tun da tsararrun ethanol daga ECR sun raba tsaka-tsaki na tsaka-tsaki tare da C2H4 wato * C2H3O (43), zaɓin hydrogenation na wannan matsakaici zai iya canza hanyoyin ECR daga C2H4 zuwa alcohols (64).Koyaya, a yawancin tsarin, zaɓin zuwa C2+ oxygenates ya fi ƙasa da hydrocarbons (31, 37, 39, 41, 42, 67).Don haka, a cikin wannan sashe, za mu haskaka dabarun ƙira na electrocatalyst waɗanda zasu iya cimma ban sha'awa C2+ oxygenate FE sama da 25%.

Kamar yadda aka tattauna a sama, ƙwaƙƙwaran ƙirar bimetallic masu haɓakawa na iya haɓaka zaɓi da aiki don samar da C2+ hydrocarbon.Hakanan an yi amfani da dabarar irin wannan amma ba iri ɗaya ba don haɓaka aikin electrocatalytic don C2+ oxygenates (38, 93, 94).Misali, Ag-incorporated Cu-Cu2O catalysts sun nuna zaɓin ethanol mai iya canzawa, kuma mafi girman ethanol FE shine 34.15% (95).Iyakar biphasic a cikin haɗin gwargwado na Ag-Cu, maimakon Ag/C atomic rabo, an gano shi azaman maɓalli na zaɓin samar da ethanol.Tun da shafin Cu yana kusa da rukunin Ag a cikin tsari mai haɗaɗɗiyar lokaci (Ag-Cu2OPB), ƙimar samuwar matsakaicin ethanol don samfurin da aka haɗa lokaci-lokaci ana iya haɓakawa idan aka kwatanta da wanda aka raba lokaci (Ag-Cu2OPS). ), yana haifar da ingantaccen aikin samar da ethanol.Bayan ethanol, Cu-Ag bimetallic NPs kuma an nuna su don canza CO2 zuwa acetate tare da ƙari na benzotriazole (93).A -1.33 V tare da RHE, FE na acetate shine 21.2%.An gabatar da hanyoyin da za a iya ɗauka guda biyu a cikin wannan yanayin: Ɗayan yana dogara ne akan CO dimerization, ɗayan kuma yana kan shigar da CO, yana nuna muhimmiyar rawar da aka samu na tsaka-tsakin CO akan shafukan Ag masu aiki.An ba da rahoton irin wannan kallo a cikin masu haɓaka Cu-Zn (Fig. 6, A da B) don samar da ethanol (38).Ta hanyar daidaita abubuwan da ke cikin Zn a cikin Zn-Cu alloyed masu haɓakawa, rabon ethanol da C2H4 FE za a iya sarrafa shi da kyau a cikin kewayon 0.48 zuwa 6, yana ba da shawarar mahimmancin wuraren haɓaka CO don haɓakar C2+ oxygenate.Ƙirƙirar abubuwan haɓakawa na iya haifar da tasiri a kan kayan matrix, wanda ba za a so wani lokaci ba.Don haka, hanyar kai tsaye zuwa masu haɓaka bimetallic na iya zama mafi dacewa ga wasu samfuran da aka yi niyya.Jaramillo da abokan aiki (96) sun gina ingantaccen tsarin bimetallic na Au-Cu, wanda aka haɗa ta hanyar saka NPs na gwal kai tsaye akan foil polycrystalline Cu, don bincika tasirin catalysis na tandem.Au-Cu bimetallic ya baje kolin zaɓi na aiki tare da C2+ barasa, wanda ya zarce tagulla da zinariya tsantsa, da kuma Au-Cu gami.Idan aka kwatanta da Cu foil, tsarin bimetallic Au-Cu ya nuna karuwar CO na gida saboda kasancewar Au NPs (Fig. 6C) waɗanda ke aiki don tsara CO.Tunda zinari baya aiki don rage CO, haɓaka ƙimar samar da barasa na C2+ akan abubuwan haɓaka bimetallic na Au-Cu an danganta shi da injin catalysis na tandem.Musamman, NPs na zinari na iya haifar da babban taro na CO na gida kusa da saman Cu.Bayan haka, za a iya ƙara yawan ƙwayoyin CO na gida zuwa C2+ ta hanyar Cu.

(A zuwa C) Alloy effects.(A) Matsakaicin FE na ethanol da C2H4 da FE rabo na ethanol da ethylene akan daban-daban Cu-Zn gami.(B) Ƙirar ƙarancin ethanol na yanzu akan nau'ikan Cu-Zn gami.(A) da (B) ana sake yin su tare da izini daga American Chemical Society (38).(C) rage CO2 da ƙimar juyin halittar CO akan zinari, jan ƙarfe, da tsarin bimetallic na Au-Cu.An sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (96).(D zuwa L) Ilimin halitta ko tasirin tsari.(D) Misalin tsari na hanyar hawan keke na ƙarfe ion.(E da F) Hotunan SEM na 100-cycle Cu kafin (E) da kuma bayan (F) ƙaddamarwa a ƙarƙashin yanayin ECR.(G) TEM da rarrabuwar wutar lantarki da aka zaɓa sun ba da shawarar cewa an fallasa Cu (100) da (H) makamashi kyauta don * OCCO da * samuwar OCCHO akan Fuskokin Cu (100), Cu (111), da Cu (211).(D) zuwa (G) ana sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (42).(I) Ratio na oxygenates da hydrocarbons a matsayin aikin yuwuwar akan Cu (111), Cu (751), da Cu (100).(J) Lambobin daidaitawa na Cu (111), Cu (100), da Cu (751).(I) da (J) ana sake bugawa tare da izini daga Kwalejin Kimiyya ta Kasa (97).(K) Tsarin tsarin canji daga Cu NPs zuwa tagulla mai siffar cubic.An sake bugawa tare da izini daga Cibiyar Nazarin Kimiyya ta Kasa (98).(L) Hotunan SEM na jan karfe na nanodendritic kafin da bayan ECR.An sake bugawa tare da izini daga Ƙungiyar Kimiyya ta Amirka (99).

An nuna zaɓaɓɓen bayyanar fuskokin kristal don electrocatalysts azaman ingantacciyar hanya mai sauƙi don cimma ingantaccen FE zuwa takamaiman samfuran ECR da kuma hanya mai mahimmanci don fahimtar asali.Sauƙaƙe amma mai iya daidaita ƙirƙira na masu kara kuzari guda-crystal yana da ƙalubale.An yi wahayi zuwa ga hanyar galvanostatic caji-fitarwa (GCD) don batura, ƙungiyarmu ta ɓullo da hanyar hawan keke na ƙarfe (Fig. 6D) don zaɓen fallasa fuskar crystal na mai ƙara kuzari (42).Bayan 100 GCD hawan keke, wani m Cu nanocube tsarar da aka kafa a kan Cu foil tare da fallasa (100) facets (Fig. 6, E zuwa G).Mai haɓaka sake zagayowar 100 ya gabatar da cikakken C2 + barasa FE na fiye da 30% da daidaitaccen adadin barasa na yanzu na C2 + fiye da 20 mA cm-2.Duk da haka, 10-cycle Cu tare da ƙananan rabo na (100) facet kawai ya ba da C2 + barasa FE na ~ 10%.DFT simulation ya tabbatar da cewa Fuskokin Cu (100) da taku (211) sun fi dacewa ga C─C haɗin kai akan Cu (111), kamar yadda aka nuna a cikin siffa 6H.An yi amfani da ƙirar ƙirar ƙira, fim ɗin epitaxial Cu tare da fuskoki daban-daban da aka fallasa, an yi amfani da su don ƙayyade abubuwan da ake amfani da su na wurin aiki zuwa C2 + samar da oxygenate (Fig. 6I) (97).Tun da yake yana da ƙasa da yuwuwar CO * dimer ya kasance kusa da atom ɗin H * akan saman tare da ƙananan maƙwabta, ƙananan rukunin yanar gizon Cu na iya hana samuwar hydrocarbons kuma haifar da ingantaccen C2 + oxygenate FE saboda yana da wahala ga hydrogenate. C─C haɗe-haɗe ECR matsakaici a saman sa (97).A cikin binciken fim na epitaxial Cu, mawallafa sun tabbatar da cewa ECR a kan Cu (751) facet ya nuna ingantaccen tsarin oxygenate / hydrocarbon.Ana iya danganta wannan haɓakawa zuwa saman Cu atom geometry na fuskoki daban-daban na Cu facets da madaidaicin matsakaicin matsakaicin matsakaicin lamba (Fig. 6J), inda Cu atom ya daidaita, bi da bi, tare da maƙwabta biyu, huɗu, da shida mafi kusa akan Cu(751). Cu (100), da Cu (111) fuska.Hakanan an yi amfani da sake gina ilimin halittar jiki don inganta C2+ oxygenate FE.Yang da abokan aiki (98) ne suka ɓullo da ƙwaƙƙwaran kubu-kamar Cu mai haɓakawa, wanda ya nuna ingantaccen aikin haɗin gwiwar C─C.A daki-daki, monodisperse Cu NPs (6.7 nm) tare da lodi daban-daban an ajiye su a kan tallafin takarda na carbon a matsayin mai kara kuzari ga ECR.Babu shakka, an lura da karuwar FE na C2 + oxygenates tare da karuwa a cikin nauyin Cu NP.An nuna cewa Cu NPs cike da yawa a ƙarƙashin babban yanayin lodi da aka yi a cikin yanayin canjin yanayin yanayi yayin ECR, wanda a ƙarshe aka samar da nau'ikan nau'ikan nau'ikan nau'in cube (Fig. 6K).An gano wannan sabon tsarin da ya fi ƙarfin lantarki.Binciken Tafel ya ba da shawarar cewa dimerization CO shine mataki na ƙayyade ƙimar samfurin C2, yayin da na n-propanol ya nuna hanya mai hankali a cikin wannan tsarin haɓakawa.Nanodendritic jan karfe wani misali ne wanda ke nuna mahimmancin sarrafa ilimin halittar jiki don samar da C2 + oxygenate (99).A taƙaice, jimillar FE na nanodendrite na jan ƙarfe da aka ƙayyade (Fig. 6L) don C2 + barasa ya kasance kusan 25% a -1.0 V tare da RHE.Wani ban sha'awa n-propanol FE na 13% za a iya samu a -0.9 V. Idan akai la'akari da babban aiki na Cu atom, jan karfe na tushen catalysts ko da yaushe suna fama da lalacewar tsarin a lokacin ECR, musamman ma a high overpotential, wanda, bi da bi, take kaiwa zuwa matalauta. kwanciyar hankali.Duk da haka, irin wannan jan karfe na nanodendritic ya nuna kyakkyawan kwanciyar hankali don samar da barasa, yana nuna barasa FE na ~ 24% akan 6 hours.

Rashin lahani na electrocatalysts, irin su atom vaccancies da dopants, suna nuna yiwuwar ƙaddamar da tsaka-tsakin ECR marasa daidaituwa kuma, don haka, zaɓin haɓaka hanyar da ta dace zuwa oxygenates (29, 43, 100).Ɗaukar * C2H3O a matsayin misali, wanda shine yiwuwar tsaka-tsakin tsaka-tsakin tsaka-tsakin don samar da ethylene da ethanol, Sargent da abokan aiki (43) sunyi nazarin rawar da lahani a cikin core-shell Cu electrocatalyst daki-daki.A ka'idar sun nuna cewa matakan makamashi na amsawa don haɓakar ethylene da ethanol sun kasance iri ɗaya a farkon matakin haɗin C─C (0.5-V overpotential) (Fig. 7A).A karkashin irin wannan yanayin, ƙaddamar da guraben jan karfe zai ɗan ƙara ƙarfin shingen makamashi don samar da ethylene, duk da haka bai nuna wani tasiri a kan tsararrun ethanol ba (Fig. 7B).Duk da haka, kamar yadda aka nuna a cikin siffa 7C, jan karfe mai kara kuzari tare da guraben aiki da sulfur dopant na karkashin kasa na iya kara girman shingen makamashi don hanyar ethylene, yana mai da shi yanayin zafi mara kyau.Duk da haka, irin wannan gyare-gyare ya nuna sakamako mara kyau a kan hanyar ethanol.An ƙara tabbatar da wannan lamarin ta hanyar gwaji.Cu2S-Cu da aka ƙera babban harsashi tare da ɗimbin guraben sarari (Cu2S-Cu-V; Hoto 7D) an haɗa shi.Adadin barasa zuwa ethylene ya karu daga 0.18 akan bare Cu NPs zuwa 0.34 akan Cu2S-Cu mara izini sannan zuwa 1.21 akan Cu2S-Cu-V, kodayake jimillar FE na samfuran C2+ ga duk masu haɓakawa sun kasance iri ɗaya (Fig. 7E) .Wannan abin lura ya nuna cewa haɓakar zaɓin barasa yana da alaƙa da ƙaddamar da samar da ethylene, daidai da sakamakon DFT.Bugu da kari, injiniyan lahani yana taka muhimmiyar rawa ga mai kara kuzari mara karfe tunda tsarkakakken kayan carbon ba sa aiki ga ECR.An yi amfani da Dopants irin su nitrogen da boron don canza tsarin lantarki na tushen kuzari (31, 43, 100).Misali, fim din nanodiamond-doped nanodiamond (NDD) a kan silinda ya keɓanta da Quan et al.(29) don zaɓin acetate samarwa daga ECR (Fig. 7F).Matsakaicin farawar acetate ya kasance ƙasa da -0.36 V tare da RHE ta amfani da mai haɓaka NDD, kuma FE don acetate ya fi 75% a cikin yuwuwar kewayon daga -0.8 zuwa -1.0 V tare da RHE.Don fahimtar asalin irin wannan ci gaba mai ban sha'awa, NDD / Si electrodes tare da nau'in nitrogen daban-daban ko nau'in nitrogen an shirya da bincike (Fig. 7G).Marubutan sun kammala da cewa mafi girman aikin NDD/Si ​​mai haɓakawa na ECR ana iya danganta shi da babban ƙarfinsa don haɓakar hydrogen da N doping, inda nau'in N-sp3C ke aiki sosai don samar da acetate.Bayanan Electrokinetic kuma a cikin situ infrared spectrum sun bayyana cewa babbar hanyar samar da acetate na iya zama CO2 → * CO2− → * (COO) 2 → CH3COO-.Bayan nitrogen, boron shine wani ingantaccen binciken heteroatom don daidaita tsarin lantarki na nanodiamond.Koyaya, boron-doped nanodiamond (BDD) an fi son rage CO2 zuwa formaldehyde ko formate (101).Bugu da ƙari kuma, Quan da abokan aiki (102) sun nuna cewa boron da nitrogen co-doped nanodiamond (BND) sun nuna tasirin haɗin gwiwa akan ECR, wanda zai iya shawo kan iyakancewar BDD sannan kuma ya samar da ethanol.BND1, BND2, da BND3 masu kara kuzari tare da abun ciki na nitrogen daban-daban da irin matakan doping na boron an shirya su.Kamar yadda aka nuna a cikin siffa 7H, mafi girman zaɓi na ethanol har zuwa 93% za'a iya samun nasara akan mai kara kuzari na BND3 a -1.0 V da RHE, wanda ke da mafi girma na nitrogen doping.Ƙididdigar ka'idar ta nuna cewa tsarin haɗin gwiwar C─C akan BND ya kasance mai dacewa da yanayin zafi, inda boron zarra ya inganta kama CO2 da nitrogen dopant ya sauƙaƙe hydrogenation na tsaka-tsakin zuwa ethanol.Ko da yake heteroatom-doped nanodiamond yana da ikon canza CO2 zuwa multicarbon oxygenates tare da babban zaɓi, ayyukan ECR ɗin sa yana da iyaka sosai saboda jinkirin tsarin canja wurin caji (yawan halin yanzu bai wuce 2 mA cm-2).Abubuwan da ke tushen graphene na iya zama mafita mai yuwuwar shawo kan gazawar tushen lu'u-lu'u.A ka'ida, an ɗauki rukunin pyridinic N gefen a cikin layin graphene azaman wuraren aiki don haɗakar C─C (103).Wannan shi ne saboda gaskiyar cewa kasancewar pyridinic N a wuraren da ke gefen zai iya canza CO2 zuwa CO, wanda za'a iya ƙarawa a cikin kwayoyin C2 + (Fig. 7I).Misali, matsakaicin * C2O2 zai iya daidaitawa a cikin carbon-doped carbon wanda a cikinsa ƙwayoyin C guda biyu ke haɗe zuwa pyridinic N da maƙwabcinsa C atom, bi da bi (103).Daga nan aka inganta hasashen ka'idar ta amfani da sinadarin nitrogen-doped graphene quantum dot (NGQD) mai kara kuzari (31).Bayan ƙaddamar da zane-zane na graphene na nitrogen-doped (1 zuwa 3 μm) (Fig. 7J), 1- zuwa 3-nm NGQDs an samo su wanda yawancin pyridinic N a wuraren da ke gefen ya karu da umarni uku na girma.A -0.78 V da RHE, matsakaicin FE don C2 + oxygenates zai iya kaiwa zuwa 26%.Bugu da ƙari, kamar yadda aka nuna a cikin Fig. 7K, ƙananan halin yanzu na C2 + oxygenates yana kusa da 40 mA cm-2 a -0.86 V tare da RHE, wanda ya fi girma fiye da nanodiamond da aka gyara.A kwatancen, N-free graphene quantum dige da N-doped graphene oxide, wanda ke nuna ƙananan gefen pyridinic N, da farko ya samar da H2, CO, da tsari.

(A zuwa C) Gibbs makamashi kyauta daga *C2H3O zuwa ethylene da ethanol don jan ƙarfe, jan ƙarfe tare da sarari, da jan ƙarfe tare da sarari jan karfe da sulfur na ƙasa.(D) Misalin tsari na Cu2S-Cu-V mai kara kuzari.(E) FE na C2 + alcohols da ethylene, kazalika da rabon FE na alcohols zuwa alkenes.(A) zuwa (E) ana sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (43).(F) Hoton SEM na NDD.(G) Yawan samarwa na acetate da formate akan NDD tare da abun ciki na nitrogen daban-daban.a %, atomic %.(F) da (G) ana sake yin su tare da izini daga American Chemical Society (29).(H) FEs na NDD, BDD, da BNDs a -1.0 V. An sake bugawa tare da izini daga John Wiley da Sons (102).(I) Misalin tsari na wuraren aiki don haɗin gwiwar C─C a cikin NGQDs.(I) an sake buga shi tare da izini daga American Chemical Society (103).(J) Hoton TEM na NGQDs.Matsakaicin sanduna, 1 nm.(K) Ƙimar ɓangarorin yanzu don samfura daban-daban ta amfani da NGQDs.(J) da (K) ana sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (31).

Bayan electrocatalysts, electrode da catalytic reactor architecture design suna gabatar da wata hanya mai tasiri don haɓaka aikin ECR, musamman don yawan samarwa da ƙarfin kuzari.An sami ci gaba mai mahimmanci akan ƙira da ƙirƙira na sabon tsarin samar da wutar lantarki don cimma ingantaccen samar da C2+.A cikin wannan sashe, za mu tattauna da ECR electrode/reactor zane daki-daki.

Kwayoyin nau'in nau'in H ana amfani da su sosai a cikin gwaje-gwaje-biyu, la'akari da haɗarsu, aiki mai sauƙi, da ƙarancin farashi.Kwayoyin suna sanye take da cathode masu zaman kansu da ɗakunan anode waɗanda ke haɗe da membrane-musanya ion (104, 105).Babban hasara na wannan nau'in tantanin halitta H shine ƙananan ƙarancin CO2 a cikin ruwa mai ruwa, wanda shine kawai 0.034 M a ƙarƙashin yanayin yanayi, yana haifar da iyakancewar CO2 rage yawan adadin halin yanzu na j <100 mA cm-2 (64).Bugu da ƙari, wasu abubuwan da ke da alaƙa, ciki har da iyakataccen yanki na lantarki da kuma babban nisa na interelectrode, sun kasa cika buƙatun bincike na girma (105, 106).Don samar da samfur na C2 +, nau'in nau'in H-nau'in yawanci suna nuna ƙarancin zaɓi a ƙarƙashin manyan abubuwan haɓakawa, misali, 32% don ethylene a -0.98 V da RHE (107), 13.1% don n-propanol a -0.9 V tare da RHE (99), da kuma 20.4% don ethanol a -0.46 V da RHE (108), saboda tsananin gasa juyin halittar hydrogen.

Don magance abubuwan da ke sama, an ba da shawarar mai sarrafa kwarara (15, 109).A cikin sel masu gudana, ana iya amfani da rafin CO2 na gas kai tsaye azaman kayan abinci a cathode, don haka yana haifar da ingantaccen ingantaccen yaduwar taro da ƙimar samarwa (104, 110).Hoto 8A yana nuna tsarin gine-gine na yau da kullun na tantanin halitta mai gudana, inda membrane na polymer electrolyte membrane (PEM) yayi aiki azaman mai raba wutar lantarki wanda aka yi sandwiched tsakanin tashoshi biyu masu gudana.Mai kara kuzari ba shi da motsi a kan na'urar watsa iskar gas (GDE) don yin aiki azaman lantarki na cathode, wanda ake ciyar da iskar gas CO2 kai tsaye.Catholyte, kamar 0.5 M KHCO3, yana ci gaba da gudana a cikin bakin bakin ciki Layer tsakanin lantarki mai kara kuzari da PEM.Bugu da kari, gefen anode yawanci ana yaduwa tare da ruwa mai ruwa-ruwa don amsawar juyin halittar oxygen (43, 110).Idan aka kwatanta da nau'in nau'in nau'in H, waɗannan sel masu gudana na tushen membrane suna nuna kyakkyawan aikin ECR.Alal misali, Sargent da abokan aiki (43) sun kimanta aikin ECR na Cu2S-Cu-V mai haɓakawa a cikin nau'in nau'in nau'in nau'in H da kuma tantanin halitta, kamar yadda aka nuna a cikin siffa 8 (B zuwa E).Yin amfani da nau'in nau'in H, matsakaicin FE don samfuran C2 + shine 41% tare da jimlar halin yanzu na ~ 30 mA cm-2 ƙarƙashin -0.95 V tare da RHE.Koyaya, FE don samfuran C2 + sun karu zuwa 53% tare da jimlar yawan yau da kullun cikin sauƙin wuce 400 mA cm-2 ƙarƙashin -0.92 V da RHE a cikin tsarin gudana.Irin wannan gagarumin ci gaban aiki ta amfani da mai sarrafa kwararar ruwa za a iya danganta shi da ingantaccen watsawar CO2 da kuma danne halayen gefe, galibi ya samo asali daga gine-ginen gas-electrolyte-catalyst na gida uku.

(A) Jadawalin ma'aunin lantarki mai gudana tare da zuƙowa-cikin ƙirar ƙirar lantarki-electrolyte.(A) an sake bugawa tare da izini daga John Wiley da Sons (30).(B zuwa E) Kwatanta aikin ECR ta amfani da nau'in tantanin halitta H da tantanin halitta.(B) zuwa (E) ana sake bugawa tare da izini daga Ƙungiyar Bugawa Nature (43).(F zuwa H) Electrolytes daban-daban da aka yi amfani da su a cikin sel masu gudana tare da aikin ECR.(F) zuwa (H) ana sake bugawa tare da izini daga John Wiley da Sons (30).(I zuwa K) Tsarin aiki da kwanciyar hankali na injin watsa wutar lantarki na tushen polymer.(I) zuwa (K) ana sake bugawa tare da izini daga AAAS (33).

Tantanin tazarar sifili wani nau'i ne na masu amfani da lantarki da ke fitowa, wanda ke ƙara cire tashoshi masu gudana a cikin sel masu gudana kuma yana danna na'urori biyu tare da membrane na musayar ion a tsakanin.Wannan tsarin zai iya rage yawan canja wurin taro da juriya ta hanyar lantarki kuma don haka inganta ingantaccen makamashi, yana sa ya fi dacewa a aikace-aikace masu amfani (110).Abubuwan da aka ciyar da su zuwa cathode na iya zama ko dai CO2-cikakken catholyte ko rafin CO2 mai humidified.Ruwan tururi ko mai ruwa mai ruwa ana ciyar da su zuwa ga anode don sakin proton don rama cajin nau'in rage CO2 (111).Gutiérrez-Guerra et al.(109) kimanta aikin haɓakar haɓakar haɓakar Cu-AC a cikin tantanin halitta sifili kuma ya ruwaito cewa acetaldehyde shine babban samfuri tare da babban zaɓi na 60%.A matsayin wani fa'ida na wannan na'urar, yana da sauƙin matsawa kwararar mai amsawa kuma yana haɓaka ƙimar CO2 na gida sosai, don haka yana haifar da manyan ƙima na yanzu da ƙimar amsawa (110).Koyaya, haɓakar canjin ion a cikin sel tazara na sifili yana ƙoƙarin yin acidify da katolite, yana mai da martani ga juyin halittar H2 maimakon rage CO2 (112).Don magance wannan matsala, Zhou da abokan aiki (112, 113) sun sanya wani shinge mai shinge tare da zazzagewar ruwa mai ruwa tsakanin cathode da membrane don kula da pH mai kyau kusa da cathode don rage amsawar CO2.Ko da yake an gano samfuran C2 + daban-daban bisa ga sel sifili, gami da acetone, ethanol, da n-propanol, FEs har yanzu suna da ƙasa kaɗan.Yawancin binciken da aka ruwaito koyaushe suna mai da hankali kan samfuran C1 waɗanda ke haɗa da ƙarancin lambobi na proton da canja wurin wutar lantarki yayin ragi.Sabili da haka, yuwuwar ƙwayar tazara ta sifili don samfuran C2+ har yanzu yana ƙarƙashin muhawara (110).

Haka kuma, sel microfluidic electrolytic (MECs) wani nau'i ne na daidaitawar lantarki mai ban sha'awa wanda Kenis da abokan aiki suka haɓaka (39, 114).A cikin wannan na'urar, ana maye gurbin membrane da wuri na bakin ciki (<1 mm a cikin kauri) cike da rafi na electrolyte don raba anode da cathode.Kwayoyin CO2 na iya bazuwa cikin sauri cikin mahaɗar lantarki-electrolyte kusa da cathode, kuma ƙayyadaddun GDEs guda biyu ana goge su ta hanyar electrolyte mai gudana.Idan aka kwatanta da ƙwayoyin kwarara na tushen membrane, MECs ba wai kawai suna guje wa babban farashin membrane ba har ma suna rage sarrafa ruwa, wanda ke nufin bushewar anode da ambaliya ta cathode lokacin da ake sarrafa su a manyan abubuwan da ke faruwa a halin yanzu saboda ja da osmotic na kwayoyin ruwa tare da. jigilar proton daga anode zuwa cathode a fadin membrane (115).Kamar yadda muka sani, duk da fa'idodi da nasarorin da aka samu, ƙaramin adadin karatu sun sami samfuran C2+ a cikin ainihin MECs.Wataƙila wannan yana faruwa ne ta hanyar tasirin "mai iyo" wanda protons da aka kafa a cikin anode suna cikin sauƙi daga wurin da ke kusa da cathode ko kuma wanke shi ta hanyar electrolyte mai gudana, maimakon shiga cikin proton da yawa da ake bukata na C2+.Ana iya tabbatar da hasashe ta misali mai zuwa.A cikin 2016, Kenis da abokan aiki (31) sun ba da rahoton nasarar rage CO2 zuwa samfuran C2 + akan gyare-gyaren da ke ɗauke da MEC, wanda NGQDs zai iya rage ƙwayoyin CO2 zuwa C2 + tare da 55% FE (31% don ethylene, 14% don ethanol, 6% don acetate, da 4% don n-propanol) a cikin yiwuwar amfani da -0.75 V tare da RHE a cikin 1 M KOH bayani.Yana da mahimmanci a nuna cewa yanayin electrolyte zai iya tasiri sosai ga zaɓin samfurin kuma.Alal misali, Jiao da abokan aiki (30) sun haɗa na'urar nanoporous Cu mai kara kuzari sannan kuma sun gwada aikin ECR ta amfani da electrolytes daban-daban (KHCO3, KOH, K2SO4, da KCl) a cikin MEC na tushen membrane.Sun bayyana cewa rage CO2 a cikin alkaline electrolyte (KOH) yana nuna mafi girman zaɓi na C2 + da yawa na yanzu, kamar yadda aka nuna a cikin siffa 8 (F da G).A -0.67 V tare da RHE a cikin 1 M KOH electrolyte, FE da aka samu don C2 + ya kai har zuwa 62% tare da ƙarancin halin yanzu na 653 mA cm-2, wanda shine mafi girma na halin yanzu wanda aka taba bayar da rahoto a cikin ragi na CO2 na lantarki. zuwa samfuran C2+.Ethylene (38.6%), ethanol (16.6%), da n-propanol (4.5%) sune manyan samfuran C2 + tare da ƙaramin adadin acetate.Har ila yau, sun nuna cewa akwai dangantaka mai karfi tsakanin pH da aka ƙididdigewa da FE don samfurori na C2 +: Mafi girman pH, mafi girma na halin yanzu da samfurori na C2 +, kamar yadda aka nuna a cikin siffa 8H.Ƙididdigar ƙa'idar ta ba da shawarar cewa OH- ions na kusa-sashen zai iya sauƙaƙe haɗin C─C (31).

Baya ga daidaitawar electrolyzer, electrolyte ɗin da aka yi amfani da shi a cikin na'urorin lantarki daban-daban na iya canza canjin samfuran ECR na ƙarshe.Kamar yadda muka ambata a sama, ana amfani da mafita na KOH na alkaline koyaushe a cikin sel masu gudana tare da kyakkyawan aiki maimakon a cikin nau'in nau'in H.An danganta shi da gaskiyar cewa KOH electrolyte zai iya samar da mafi girman halayen lantarki, rage juriya na ohmic tsakanin murfin lantarki na bakin ciki akan mai kara kuzari da kuma yawan electrolyte, kuma ya kara rage abubuwan da ake bukata don samuwar C2+ (31).Sakamakon DFT ya kara tabbatar da cewa kasancewar OH- ions zai iya rage shingen makamashi don dimerization na CO, don haka yana ƙarfafa samuwar C2 + da kuma murkushe gasar daga samuwar C1 da H2 (30, 33).Koyaya, KOH alkaline ba za a iya amfani dashi azaman electrolyte a cikin nau'ikan nau'ikan H ba.Wannan saboda CO2 rafukan za su yi sauri da sauri tare da mafita na KOH kuma a ƙarshe ƙirƙirar maganin bicarbonate tare da pH tsaka tsaki a cikin nau'in nau'in H (30).A cikin sel masu gudana, duk da haka, da zarar CO2 ya bazu ta hanyar GDE, za a cinye kwayoyin CO2 a cikin iyakokin iyaka sau uku (CO2-catalyst-electrolyte) don samar da samfuran ragewa nan da nan.Bayan haka, ƙarancin buffering na electrolyte yana iya haɓaka pH da sauri a kusa da lantarki a cikin jeri na lantarki na lantarki, yayin da wutar lantarki da ke gudana za ta wartsake saman kuma rage girman canjin pH a cikin electrolyte (33, 116).

Kamar yadda aka ambata a baya cewa ECR shine amsawar da ke sarrafa yaduwa, babban matsin lamba kuma zai iya haɓaka babban taro da haɗin gwiwar CO2.Matsakaicin matsi na yau da kullun suna kama da autoclave na bakin karfe, wanda za'a iya shigar da CO2 mai ƙarfi (har zuwa 60 atom) a cikin tantanin halitta, wanda ke haifar da haɓaka mai ban mamaki a cikin FE da ƙimar yanzu na C2+ (117). , 118).Sakata da abokan aiki (119) sun nuna cewa za'a iya inganta yawan halin yanzu zuwa 163 mA cm-2 a ƙarƙashin 30 atm akan wani Cu electrode tare da ethylene a matsayin babban samfurin.Yawancin masu haɓaka ƙarfe (misali, Fe, Co, da Ni), ba tare da wani aiki don samar da C2 + a matsa lamba na yanayi ba, na iya rage CO2 zuwa ethylene, ethane, propane, da sauran samfuran C2+ masu girma a matsi mai ƙarfi.An nuna cewa zaɓin samfuran ya dogara sosai akan matsa lamba CO2 a cikin yanayin canjin samuwar CO2 a farfajiyar lantarki (117, 120).Babban samfuran da aka rage ana canza su daga H2 zuwa hydrocarbons (C2+ sun haɗa) kuma a ƙarshe zuwa CO/HCOOH tare da ƙarar CO2 matsa lamba.Musamman ma, ya kamata a kula da matsa lamba na CO2 a hankali saboda matsananciyar CO2 mai girma ko ƙananan matsa lamba zai haifar da wuce gona da iri ko iyakancewar ƙimar CO2, wanda ke nuna fifikon samar da CO/HCOOH ko H2.Madaidaicin adadin matsakaicin CO na yanzu da yawa na yanzu wanda aka haifar akan farfajiyar lantarki zai iya sauƙaƙe aikin haɗin gwiwar C─C da haɓaka zaɓin samfur na C2+ (119).

Zayyana na'urar lantarki na labari tare da ci-gaba sifofi wani muhimmin alkibla ne don haɓaka zaɓin samar da C2+.A farkon matakin, na'urorin lantarki masu aiki ba su da ƙarfi na ƙarfe kuma suna fama da jinkirin canja wurin taro (26, 105).Sakamakon haka, an ba da shawarar GDE don rage ƙarancin aikin tantanin halitta ta hanyar samar da tashoshi na hydrophobic waɗanda ke sauƙaƙe yaduwar CO2 zuwa ƙwayoyin cuta (121).GDE na al'ada yawanci ya ƙunshi Layer mai ƙara kuzari (CL) da Layer diffusion Layer (GDL), kamar yadda aka nuna a ƙananan ɓangaren siffa 8A (30, 33).Gas-liquid-catalyst interface da aka kafa a cikin GDE yana da mahimmanci don inganta aikin tantanin halitta.GDL da aka haɗe tare da kayan porous (yawanci takarda carbon) na iya samar da wadatattun hanyoyin CO2 da kuma tabbatar da saurin yaduwar wutar lantarki.Hakanan yana aiki azaman matsakaicin matsakaicin jigilar juriya don protons, electrons, da samfuran ragewa daga CL zuwa cikin electrolyte (121).Zubar da simintin gyare-gyare, buroshin iska, da lantarki sune fasahohin gama gari don shirya GDEs (122).Masu haɓakawa da aka haɗa tare da GDEs an bincika su sosai a cikin CO2 electroreduction zuwa samfuran C2+.Musamman ma, sel masu kwarara da aka ambata tare da kyakkyawan aiki duk suna haɗe da GDEs.A farkon 1990, Sammells da abokan aiki (123) sun ba da rahoton cewa GDEs masu rufi sun sami babban FE na 53% don ethylene tare da babban nauyin 667 mA cm-2.Haɓaka zaɓin ethylene da ethanol babban ƙalubale ne wanda koyaushe ana haɗa shi akan abubuwan haɓakawa na tushen Cu saboda hanyoyin halayen injina iri ɗaya.Bugu da ƙari, yana da mahimmanci a nuna cewa haɓakar haɓakawa da zaɓi na ethylene idan aka kwatanta da ethanol an lura da su akan GDE na tushen Cu (25, 36).Gewirth da abokan aiki (36) sun nuna kyakkyawan FE na 60% don ethylene da FE don ethanol na 25% akan electrodeposited Cu-Ag GDE, lokacin da yawan adadin halin yanzu ya kai ~ 300 mA cm-2 a -0.7 V tare da -0.7 V. RHEAiki ne da ba kasafai ba wanda ya sami irin wannan babban zaɓi a babban yawan halin yanzu.Wannan binciken yana nuna cewa na'ura mai haɗawa ta GDE tana ba da kyakkyawar hanya don daidaita hanyoyin amsawa, wanda za'a iya samun zaɓi na samfuran da aka rage a babban adadin yanzu.

Zaman lafiyar GDEs shima wani muhimmin batu ne wanda yakamata a magance shi saboda tsayayyen aiki na dogon lokaci yana da mahimmanci don aiwatar da aikace-aikacen sel masu gudana.Duk da fitaccen aikin CO2-zuwa-C2+ da aka samu tare da GDEs, kwanciyar hankali har yanzu ba ta da kyau saboda raunin injin manne mai kara kuzari, GDL, da yadudduka masu ɗaure (77, 124).Fuskar carbon na GDL na iya canzawa daga hydrophobic zuwa hydrophilic yayin amsawar electrochemical saboda yanayin iskar oxygen da ya faru a sama mai ƙarfi, wanda ke haifar da ambaliya a cikin GDL da toshe hanyoyin yaduwar CO2 (33).Don magance wannan matsala, masu bincike sun haɗa haɗin hydrophobic scaffold na polytetrafluoroethylene (PTFE) zuwa GDEs.Idan aka kwatanta da Nafion hydrophilic, PTFE na hydrophobic yana ba da kwanciyar hankali na dogon lokaci (33).Sargent da abokan aiki (33) sun haɗu da mai haɓaka Cu tsakanin PTFE da carbon NPs da aka raba, wanda Layer PTFE na hydrophobic zai iya lalata NPs da graphite layers, don haka gina ingantaccen tsarin lantarki (Fig. 8, I da J).A sakamakon haka, FE don samar da ethylene ya karu zuwa 70% a cikin 7 M KOH bayani a halin yanzu na 75 zuwa 100 mA cm-2.An tsawaita tsawon rayuwar wannan mai sarrafa kwarara zuwa fiye da sa'o'i 150 tare da asarar da ba ta dace ba a cikin zaɓin ethylene, wanda ya ninka sau 300 fiye da GDEs na gargajiya, kamar yadda aka nuna a cikin siffa 8K.Irin wannan tsarin sanwici an nuna shi ya zama kyakkyawan ƙirar GDE.Misali, Cui da abokan aiki (124) sun tsara tsarin trilayer tare da Layer na lantarki mai aiki wanda aka yanke ta fina-finai na polyethylene na hydrophobic nanoporous guda biyu.Yaduddukan hydrophobic na waje na iya rage jinkirin kwararar electrolyte daga babban maganin, yana haifar da karko, babban pH na gida a kusa da lantarki mai aiki.Haɓakawa na sararin interlayer, wanda zai iya inganta jigilar CO2 da tallatawa, yana da mahimmanci a cikin irin wannan zane (124).Kwanan nan, carbon nanotubes kuma an haɗa su cikin GDEs saboda girman girman su, kyakkyawan aiki, da hydrophobicity, wanda zai iya sauƙaƙe jigilar lantarki da jigilar jama'a (77).

Duk da ci gaba mai ban sha'awa akan ECR, dabarun don ƙarancin farashi, manyan samfuran samfuran C2+ ba safai suke samuwa (125).A wannan mataki, ƙalubalen da dama sun kasance tare don fahimtar hanyoyin amsawa na ECR da kuma tallata wannan fasaha mai ban sha'awa.

A matsayin kyakkyawan bayani don rufe madauki na carbon da adana makamashin da za a iya sabuntawa na lokaci-lokaci, kamar iska da hasken rana, an sami ci gaba mai yawa don cimma ingantaccen juzu'in CO2 a cikin shekarun da suka gabata.Yayin da fahimtar hanyoyin da ke da alaƙa da ECR ya zo da nisa tun farkon kwanakinsa (126), haɗin C─C ta hanyar ECR zuwa samfuran C2 + har yanzu ba a shirye don aikace-aikacen aiki ba.A cikin wannan bita, mun ɗauki cikakken nazarin dabarun na yanzu waɗanda zasu iya haɓaka zaɓin zaɓi da ƙimar samarwa don samfuran C2+ ta hanyar ECR, gami da daidaitawa mai ƙara kuzari, tasirin electrolyte, yanayin electrochemical, da ƙirar lantarki/reactor na lantarki.

Duk da ƙoƙarin da aka yi a cikin ECR, har yanzu akwai matsaloli da yawa tare da masu haɓakawa na yanzu da tsarin ECR waɗanda dole ne a magance su kafin yin kasuwanci da ECR.Na farko, a matsayin mamaye mai kara kuzari don gane ingantaccen C─C hada guda biyu, Cu yana fama da matsalolin kwanciyar hankali, musamman a cikin ruwa mai ruwa da tsaki, kuma yana iya da wuya ya rayu har tsawon sa'o'i 100 saboda girman motsin zarra, haɓakar barbashi, da lalacewar tsarin ƙarƙashin yanayin ECR.Don haka, yadda za a sami kwanciyar hankali na dogon lokaci ta amfani da mai haɓaka tushen Cu har yanzu babban kalubale ne.Ƙirƙirar mai haɓaka tushen Cu akan takamaiman tallafi tare da hulɗa mai ƙarfi na iya zama ingantaccen dabara don adana tsarin haɓakawa / ilimin halittar jiki don haka yana ba da ingantaccen tsawon rayuwa.Bugu da ƙari kuma, yin amfani da na'urar lantarki ta polymer membrane don maye gurbin maganin ruwa a lokacin ECR na iya yiwuwa ya kara inganta kwanciyar hankali na tushen Cu.Bugu da ƙari, daga mahangar masu haɓakawa, a cikin situ/a cikin operando dabarun ƙira da ƙirar ƙira ya kamata kuma a yi amfani da su don saka idanu da fahimtar lalata aikin mai kara kuzari, don haka, bi da bi, danne lalacewa da guba na mai kara kuzari zuwa mafi ƙasƙanci matakan.Wani muhimmin batu na masu kara kuzari na ECR wanda ya kamata a magance shi shine sanya ka'idar haɗakarwa mai yiwuwa don samar da taro.Don wannan, an fi son daidaita hanyoyin roba ta amfani da kayan abinci da yawa.

Na biyu, samar da C2 + oxygenated daga ECR yawanci gauraye da solutes (misali, KHCO3 da KOH) a cikin electrolyte ga gargajiya H- ko kwarara-cell reactors, wanda, duk da haka, na bukatar ƙarin rabuwa da taro tafiyar matakai don dawo da tsarki ruwa man fetur mafita a cikin. aikace-aikace masu amfani.A lokaci guda, haɓakar C2+ hydrocarbons suma suna haɗe da H2 da sauran CO2.Don haka, tsarin rabuwa mai tsada yana da mahimmanci ga fasahar ECR na yanzu, wanda ke daɗa hana ECR daga aikace-aikace mai amfani.Don haka, yadda ake samar da mafita mai tsafta da kuma ci gaba da samar da tsaftataccen ruwan mai da iskar gas mai tsafta, musamman tare da yawan samfuran samfura, yana da matuƙar kyawawa don aiwatar da aikin ECR.Don haka muna hasashen haɓakar haɓakar haɓakar samfuran kai tsaye ta hanyar ECR a nan gaba, wanda zai iya ɗaukar fasahar ECR kusa da kasuwa (127).

Na uku, yayin da samuwar C─O da C─H, irin su ethanol, acetic acid, da ethylene, a cikin fasahar ECR da aka yi nazari sosai, binciken wasu nau'ikan samfuran kuma yana da mahimmanci ga fasahar ECR kuma yana nuna sha'awar tattalin arziki.Alal misali, kwanan nan, Han da abokan aiki (128) sun ba da rahoton samar da 2-bromoethnol ta ECR.Halin da ake samu na C─Br bond yana canza samfurin daga ethanol zuwa 2-bromoethnol, wanda shine muhimmin tubalin ginin sinadarai da haɗin magunguna kuma yana nuna ƙimar da ta fi girma.Don haka, bayan samfuran C2+ da aka yi nazari sosai a halin yanzu, mun yi imanin cewa niyya ga wasu samfuran da ba kasafai ake binciko su ba kamar oxalic acid (129) da haɗaɗɗun ƙwayoyin C2+ masu rikitarwa kamar mahaɗan cyclic wata hanya ce mai ban sha'awa don binciken ECR na gaba.

Ƙarshe amma ba kalla ba, novel electrode da reactor kayayyaki irin su GDE mai hana ruwa, ƙwayoyin ruwa-ruwa, da kuma tantanin halitta PEM ya kamata a karɓa don haɓaka ƙimar samar da ECR zuwa matakin kasuwanci (> 200 mA cm-2).Duk da haka, babban bambance-bambance a cikin ayyukan electrocatalytic ana lura da shi koyaushe lokacin da ake amfani da masu amfani da wutar lantarki zuwa cikakken gwajin tantanin halitta.Sabili da haka, ya kamata a yi ƙarin nazarin tsarin don rage rata tsakanin nazarin rabin cell da aikace-aikacen na'urar cikakken cell don kawo ECR daga gwajin ma'auni zuwa amfani mai amfani.

A taƙaice, ragewar CO2 na lantarki yana ba mu dama mai kyau don tunkarar matsalar muhalli daga iskar gas da ayyukan ɗan adam ke fitarwa.Hakanan yana nuna yuwuwar cimma tsaftataccen mai da sinadarai ta amfani da makamashi mai sabuntawa.Duk da yake kalubale da yawa sun kasance ga fasahar ECR a halin yanzu, musamman ga tsarin haɗin gwiwar C ─C, an yi imanin cewa tare da ci gaba da bincike da ci gaba a kan haɓakawa na haɓakawa da kuma kammalawar kwayar halitta, hangen nesa na ainihin CO2 electrolysis don man fetur mai tsabta. kuma za'a gane sinadarai nan gaba kadan.

Wannan labarin buɗaɗɗen shiga ne wanda aka rarraba ƙarƙashin sharuɗɗan lasisin Haɗaɗɗen Haɗin Kai-NonCommercial, wanda ke ba da izinin amfani, rarrabawa, da haifuwa a kowane matsakaici, muddin sakamakon amfani da shi ba don fa'idar kasuwanci ba ne kuma idan aikin na asali ya kasance daidai. ambato.

NOTE: Muna buƙatar adireshin imel ɗin ku kawai don mutumin da kuke ba da shawarar shafin ya san cewa kuna son su gani, kuma ba saƙon takarce ba ne.Ba mu kama kowane adireshin imel ba.

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