Electroreduction of CO2 to Formate with Low Overpotential using Cobalt Pyridine Thiolate Complexes
Electroreduction of CO2 to Formate with Low Overpotential using Cobalt Pyridine Thiolate Complexes
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DOI：
10.1002/anie.202006269
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发表时间：
2020-08-13
影响因子：
16.6
通讯作者：
Mougel, Victor
中科院分区：
文献类型：
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作者：
Dey, Subal;Todorova, Tanya K.;Mougel, Victor
电催化CO2还原为增值产品提供了一种可行的替代使用来自化石燃料的碳源的方法。以合理的能量成本（例如，低过电位）进行这些转化仍然是一个挑战。分子催化剂允许通过调节其配位球和配体组来精细控制活性和选择性。在这里，我们研究了一系列的钴（III）吡啶硫醇配合物作为电催化剂的CO2还原。研究了配体和质子源对活性的影响。我们确定联吡啶双（2-吡啶硫醇）钴（III）六氟磷酸盐作为一个高选择性的催化剂甲酸生产操作在110 mV的低过电位与10 s（-1）的周转频率（TOF）。电动力学分析加上密度泛函理论（DFT）计算建立了机制的途径，突出了金属氢化物中间体的作用。该催化剂通过形成稳定的钴羰基络合物而失活，但活性物种可以在氧化和释放配位的CO配体后再生。
Electrocatalytic CO2 reduction to value-added products provides a viable alternative to the use of carbon sources derived from fossil fuels. Carrying out these transformations at reasonable energetic costs, for example, with low overpotential, remains a challenge. Molecular catalysts allow fine control of activity and selectivity via tuning of their coordination sphere and ligand set. Herein we investigate a series of cobalt(III) pyridine-thiolate complexes as electrocatalysts for CO2 reduction. The effect of the ligands and proton sources on activity was examined. We identified bipyridine bis(2-pyridinethiolato) cobalt(III) hexaflurophosphate as a highly selective catalyst for formate production operating at a low overpotential of 110 mV with a turnover frequency (TOF) of 10 s(-1). Electrokinetic analysis coupled with density functional theory (DFT) computations established the mechanistic pathway, highlighting the role of metal hydride intermediates. The catalysts deactivate via the formation of stable cobalt carbonyl complexes, but the active species could be regenerated upon oxidation and release of coordinated CO ligands.