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Enhanced photoreduction of water catalyzed by a cucurbit[8]uril-secured platinum dimer.

ABSTRACT: A cucurbit[8]uril (CB[8])-secured platinum terpyridyl chloride dimer was used as a photosensitizer and hydrogen-evolving catalyst for the photoreduction of water. Volumes of produced hydrogen were up to 25 and 6 times larger than those obtained with the corresponding free and cucurbit[7]uril-bound platinum monomer, respectively, at equal Pt concentration. The thermodynamics of the proton-coupled electron transfer from the Pt(ii)-Pt(ii) dimer to the corresponding Pt(ii)-Pt(iii)-H hydride key intermediate, as quantified by density functional theory, suggest that CB[8] secures the Pt(ii)-Pt(ii) dimer in a particularly reactive conformation that promotes hydrogen formation.

SUBMITTER: Rabbani R

PROVIDER: S-EPMC8635170 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Enhanced photoreduction of water catalyzed by a cucurbit[8]uril-secured platinum dimer.

Rabbani Ramin R Saeedi Sima S Nazimuddin Md M Barbero Héctor H Kyritsakas Nathalie N White Travis A TA Masson Eric E

Chemical science 20211104 46

A cucurbit[8]uril (CB[8])-secured platinum terpyridyl chloride dimer was used as a photosensitizer and hydrogen-evolving catalyst for the photoreduction of water. Volumes of produced hydrogen were up to 25 and 6 times larger than those obtained with the corresponding free and cucurbit[7]uril-bound platinum monomer, respectively, at equal Pt concentration. The thermodynamics of the proton-coupled electron transfer from the Pt(ii)-Pt(ii) dimer to the corresponding Pt(ii)-Pt(iii)-H hydride key inte ...[more]

PMID: 34976355

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