Gcwalisa leli fomu elingezansi futhi sizokuthumela i-imeyili inguqulo ye-PDF ethi “Ukuthuthukiswa kobuchwepheshe obusha bokuguqula i-carbon dioxide ibe uphethiloli owuketshezi”
I-Carbon dioxide (CO2) iwumkhiqizo wezibaso ezimbiwa phansi ezivuthayo kanye negesi ebamba ukushisa evame kakhulu, engaguqulwa ibuyiselwe ibe izinto zokubasa eziwusizo ngendlela eqhubekayo. Enye indlela ethembisayo yokuguqula ukukhishwa kwe-CO2 kube isitoko sikaphethiloli inqubo ebizwa ngokuthi ukuncishiswa kwe-electrochemical. Kodwa ukuze ikwazi ukuhweba, inqubo idinga ukuthuthukiswa ukuze kukhethwe noma kukhiqizwe imikhiqizo efiselekayo ecebile ngekhabhoni. Manje, njengoba kubikiwe kumagazini we-Nature Energy, i-Lawrence Berkeley National Laboratory (i-Berkeley Lab) isungule indlela entsha yokuthuthukisa ubuso be-catalyst yethusi esetshenziselwa ukusabela okusizayo, ngaleyo ndlela ikhulise ukukhetha kwenqubo.
"Nakuba sazi ukuthi ithusi liyi-catalyst engcono kakhulu yalokhu kusabela, ayinikezi ukukhetha okuphezulu komkhiqizo oyifunayo," kusho u-Alexis, usosayensi omkhulu eMnyangweni Wezesayensi Yamakhemikhali eBerkeley Lab kanye noprofesa wobunjiniyela bamakhemikhali eNyuvesi. eCalifornia, eBerkeley. Kusho uSpell. "Ithimba lethu lithole ukuthi ungasebenzisa indawo yasendaweni ye-catalyst ukwenza amaqhinga ahlukahlukene ukuze unikeze lolu hlobo lokukhetha."
Ezifundweni ezedlule, abacwaningi baye basungula izimo eziqondile ukuze banikeze indawo engcono kakhulu kagesi namakhemikhali ukuze benze imikhiqizo ecebile nge-carbon enenani lezentengiselwano. Kodwa lezi zimo ziphambene nezimo ezenzeka ngokwemvelo kumangqamuzana kaphethiloli avamile asebenzisa izinto zokuqhuba ezisekelwe emanzini.
Ukuze kunqunywe umklamo ongasetshenziswa endaweni yamanzi yamaseli kaphethiloli, njengengxenye yephrojekthi ye-Energy Innovation Center ye-Liquid Sunshine Alliance yoMnyango Wezamandla, uBell nethimba lakhe baphendukela kungqimba oluncane lwe-ionomer, oluvumela ukushajwa okuthile. ama-molecule (ama-ion) ukuze adlule. Ungafaki amanye ama-ion. Ngenxa yezindawo zabo zamakhemikhali ezikhetha kakhulu, zifaneleka kakhulu ukuba nomthelela oqinile endaweni encane.
U-Chanyeon Kim, umcwaningi we-postdoctoral eqenjini le-Bell kanye nombhali wokuqala wephepha, uhlongoze ukuthi amboze ama-copper catalysts ngama-ionomer amabili ajwayelekile, i-Nafion ne-Sustainion. Ithimba lacabanga ukuthi ukwenza kanjalo kufanele kuguqule indawo ezungezile eduze kwe-catalyst—okuhlanganisa i-pH nenani lamanzi nesikhutha—ngandlela thize ukuze kuqondiswe ukusabela ukuze kukhiqizwe imikhiqizo ene-carbon engashintshwa kalula ibe amakhemikhali awusizo. Imikhiqizo kanye namafutha e-liquid.
Abacwaningi basebenzise ungqimba oluncane lwe-ionomer ngayinye kanye nongqimba oluphindwe kabili lwama-ionomers amabili kufilimu yethusi esekelwe yi-polymer material ukuze benze ifilimu, abangayifaka eduze komkhawulo owodwa weseli ye-electrochemical emise okwesandla. Lapho bejova i-carbon dioxide ebhethrini futhi besebenzisa i-voltage, bakala inani lamanje eligeleza ebhethrini. Babe sebelinganisa igesi noketshezi oluqoqwe endaweni yokugcina amanzi eseduze ngesikhathi sokusabela. Ngecala lezendlalelo ezimbili, bathole ukuthi imikhiqizo ene-carbon ecebile ibalwa ku-80% wamandla adliwe ukusabela-okungaphezulu kuka-60% esimweni esingenalutho.
"Le sandwich enamathela inikeza okungcono kakhulu kokubili komhlaba: ukukhetha komkhiqizo ophezulu kanye nomsebenzi ophezulu," kusho uBell. I-double-layer surface ayilungile kuphela emikhiqizweni ecebile nge-carbon, kodwa futhi ikhiqiza amandla amanje anamandla ngesikhathi esifanayo, okubonisa ukwanda komsebenzi.
Abacwaningi baphetha ngokuthi impendulo ethuthukisiwe yayiwumphumela wokuhlushwa okuphezulu kwe-CO2 okuqoqwe ekugqokeni ngqo phezulu kwethusi. Ngaphezu kwalokho, ama-molecule akhokhiswa kabi anqwabelana esifundeni phakathi kwama-ionomers amabili azokhiqiza i-asidi yendawo ephansi. Le nhlanganisela iqeda ukuhwebelana okugxilile okuvame ukwenzeka uma engekho amafilimu e-ionomer.
Ukuze kuthuthukiswe ukusebenza kahle kokusabela, abacwaningi baphendukela kubuchwepheshe obufakazelwe ngaphambilini obungadingi ifilimu ye-ionomer njengenye indlela yokwandisa i-CO2 ne-pH: i-pulsed voltage. Ngokusebenzisa i-pulsed voltage ku-double-layer ionomer coating, abacwaningi bathole ukukhuphuka okungama-250% emikhiqizweni ecebile ngekhabhoni uma kuqhathaniswa ne-copper engahlanganisiwe kanye nogesi omile.
Nakuba abanye abacwaningi begxila emsebenzini wabo ekuthuthukiseni ama-catalyst amasha, ukutholakala kwe-catalyst akunaki izimo zokusebenza. Ukulawula imvelo endaweni ye-catalyst kuyindlela entsha nehlukile.
“Asizange siqhamuke ne-catalyst entsha ngokuphelele, kodwa sasebenzisa ukuqonda kwethu i-reaction kinetics futhi sasebenzisa lolu lwazi ukuze lusiqondise ekucabangeni ukuthi singayishintsha kanjani indawo yendawo ye-catalyst,” kusho u-Adam Weber, unjiniyela omkhulu. Ososayensi abasemkhakheni wobuchwepheshe bamandla e-Berkeley Laboratories kanye nombhali-ndawonye wamaphepha.
Isinyathelo esilandelayo siwukwandisa ukukhiqizwa kwama-catalysts ahlanganisiwe. Ukuhlola kokuqala kwethimba le-Berkeley Lab kuhilela amamodeli amancane ayisicaba, abelula kakhulu kunezakhiwo ezinezimbotshana zendawo enkulu ezidingekayo ekusetshenzisweni kwezentengiso. “Akunzima ukufaka i-coating endaweni eyisicaba. Kodwa izindlela zokuhweba zingabandakanya ukumboza amabhola ethusi amancane,” kusho uBell. Ukwengeza ungqimba lwesibili lwe-coating kuba yinselele. Okunye okungenzeka iwukuba uhlanganise futhi ufake lezi zingubo ezimbili ndawonye entweni encibilikayo, bese uthemba ukuthi ziyahlukana lapho isincibilikisi sihwamuka. Kuthiwani uma bengakwenzi? UBell uphethe ngokuthi: “Kudingeka sihlakaniphe kakhudlwana.” Bheka uKim C, uBui JC, uLuo X nabanye. I-catalyst microenvironment eyenziwe ngokwezifiso yokunciphisa i-electro-CO2 emikhiqizweni enekhabhoni eminingi kusetshenziswa ungqimba oluphindwe kabili lwe-ionomer enamathela ethusi. I-Nat Energy. 2021;6(11):1026-1034. doi:10.1038/s41560-021-00920-8
Lesi sihloko senziwa kabusha kusuka kokulandelayo. Qaphela: Okubalulekile kungenzeka kuhlelwe ubude nokuqukethwe. Ukuze uthole ulwazi olwengeziwe, sicela uthinte umthombo okhonjiwe.
Isikhathi sokuthumela: Nov-22-2021
