{"title":"Tuning the RWGS Reaction via EPOC and In Situ Electro-oxidationnof Cobalt Nanoparticles","authors":"Dimitrios Zagoraios (9732921), Sotirios Tsatsos (9657445), Stella Kennou (1428010), Constantinos G. Vayenas (9732924), Georgios Kyriakou (1320336), Alexandros Katsaounis (9732927)","doi":"10.1021/acscatal.0c04133.s001","DOIUrl":"https://doi.org/10.1021/acscatal.0c04133.s001","url":null,"abstract":"Thenelectrochemical promotion of catalytic activity by non-noblentransition metals is rarely reported in the literature. Here, Co nanoparticlesnwere utilized for the electrochemical activation of CO<sub>2</sub> hydrogenation under atmospheric pressure conditions. A range ofntransient kinetic experiments in conjunction with X-ray photoelectronnspectroscopy and imaging techniques were employed to correlate thenobserved catalytic activity with the electronic and morphologicalncharacteristics of the cobalt catalyst surface. Our results show thatnmigrating ions from the solid electrolyte to the catalyst surfacenhas a dual effect, which has an impact on the observed catalytic behavior.nFirst, they lead to an electrochemically formed double layer on thencatalyst surface, which effectively modifies the catalyst work functionnand consequently alters the observed catalytic rate. Second, theynhave a profound effect on the oxidation state of cobalt and thereforenon the structure of the cobalt oxide particles formed. The presencenof Co oxide phases upon anodic polarization shows up to a 5-fold increasenin the catalytic rate of the reverse water gas shift (RWGS) reaction.nThe enhancement of the catalytic activity observed in this work, withna relatively inexpensive cobalt oxide film, is comparable to thatnobtained with noble metal catalysts in classical EPOC studies. Thenpresent study also demonstrates that the formation of different oxidenphases can be controlled accurately by electrochemical means and usednto tune the catalytic activity and selectivity of cobalt. The reportednresults could guide the design and operation of more selective andnactive catalytic processes for the RWGS reaction.","PeriodicalId":522884,"journal":{"name":"Figshare","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147905367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}