Cobalt Corrole Catalyst for Efficient Hydrogen Evolution Reaction from H2O under Ambient Conditions: Reactivity, Spectroscopy, and Density Functional Theory Calculations

详细信息    查看全文

• 作者：Biswajit Mondal ; Kushal Sengupta ; Atanu Rana ; Atif Mahammed ; Mark Botoshansky ; Somdatta Ghosh Dey ; Zeev Gross ; Abhishek Dey
• 刊名：Inorganic Chemistry
• 出版年：2013
• 出版时间：March 18, 2013
• 年：2013
• 卷：52
• 期：6
• 页码：3381-3387
• 全文大小：403K
• 年卷期：v.52,no.6(March 18, 2013)
• ISSN：1520-510X

文摘

The feasibility of a hydrogen-based economy relies very much on the availability of catalysts for the hydrogen evolution reaction (HER) that are not based on Pt or other noble elements. Significant breakthroughs have been achieved with certain first row transition metal complexes in terms of low overpotentials and large turnover rates, but the majority of reported work utilized purified and deoxygenated solvents (most commonly mixtures of organic solvents/acids). Realizing that the design of earth abundant metal catalysts that operate under truly ambient conditions remains an unresolved challenge, we have now developed an electronically tuned Co(III) corrole that can catalyze the HER from aqueous sulfuric acid at as low as 鈭?.3 V vs NHE, with a turnover frequency of 600 s^鈥? and 10⁷ catalytic turnovers. Under aerobic conditions, using H₂O from naturally available sources without any pretreatment, the same complex catalyzes the reduction of H⁺ with a Faradaic Yield (FY) of 52%. Density functional theory (DFT) calculations indicate that the electron density on a putative hydride species is delocalized off from the H atom into the macrocycle. This makes the protonation of a [Co(III)-H]^{鈥?/sup> species the rate determining step (rds) for the HER consistent with the experimental data.}