{"title":"A bifunctional cobalt bis(terpyridine) complex for efficient water splitting to green hydrogen generation","authors":"Binitendra Naath Mongal , Saddam Sk , Amritanjali Tiwari , Saad Mehmood , Yarasi Soujanya , Ujjwal Pal , Malapaka Chandrasekharam","doi":"10.1016/j.nxener.2024.100116","DOIUrl":null,"url":null,"abstract":"<div><p>Photocatalytic hydrogen evolution is considered to be the holy grail of artificial photosynthesis. Here, we report a novel bifunctional Cobalt bis-(terpyridine) complex on dual role in photocatalytic and electrocatalytic hydrogen generations. The integrated Co-complex as photosensitizer attached to TiO<sub>2</sub> shows an impressive hydrogen evolution reaction rate of 715 µmol g<sup>−1</sup> h<sup>−1</sup> with a high turnover number of 5718 and apparent quantum yield of 5.34%. The co-functionalized electrode shows significantly enhanced electrocatalytic activity through proton-coupled electron transfer path in CH<sub>3</sub>CN/trifluoroacetic acid at 0.63 V with a turn-over frequency of 18.64 s<sup>−1</sup> at an optimal acid to catalyst ratio of 8:1. The electron-rich 4′-(5-(4-diphenylamino)phenylthiophen-2-yl)-2,2′:6′,2″-terpyridine π-conjugation synergistically enhances the catalytic performances and effectively transmits electronic charge to the terpyridine core via the thienyl spacer and supports mechanistic insight of the Co-center in the catalytic cycle. The simple design strategy of molecular catalysts with structural integrity is expected to offer an economically viable approach for practical energy conversion applications.</p></div>","PeriodicalId":100957,"journal":{"name":"Next Energy","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2949821X24000218/pdfft?md5=dddd1f753a8314031f21563662ef533b&pid=1-s2.0-S2949821X24000218-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Next Energy","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2949821X24000218","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Photocatalytic hydrogen evolution is considered to be the holy grail of artificial photosynthesis. Here, we report a novel bifunctional Cobalt bis-(terpyridine) complex on dual role in photocatalytic and electrocatalytic hydrogen generations. The integrated Co-complex as photosensitizer attached to TiO2 shows an impressive hydrogen evolution reaction rate of 715 µmol g−1 h−1 with a high turnover number of 5718 and apparent quantum yield of 5.34%. The co-functionalized electrode shows significantly enhanced electrocatalytic activity through proton-coupled electron transfer path in CH3CN/trifluoroacetic acid at 0.63 V with a turn-over frequency of 18.64 s−1 at an optimal acid to catalyst ratio of 8:1. The electron-rich 4′-(5-(4-diphenylamino)phenylthiophen-2-yl)-2,2′:6′,2″-terpyridine π-conjugation synergistically enhances the catalytic performances and effectively transmits electronic charge to the terpyridine core via the thienyl spacer and supports mechanistic insight of the Co-center in the catalytic cycle. The simple design strategy of molecular catalysts with structural integrity is expected to offer an economically viable approach for practical energy conversion applications.