Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, U.K.
J Am Chem Soc. 2017 May 31;139(21):7217-7223. doi: 10.1021/jacs.7b00369. Epub 2017 May 18.
Photocatalytic conversion of CO into carbonaceous feedstock chemicals is a promising strategy to mitigate greenhouse gas emissions and simultaneously store solar energy in chemical form. Photocatalysts for this transformation are typically based on precious metals and operate in nonaqueous solvents to suppress competing H generation. In this work, we demonstrate selective visible-light-driven CO reduction in water using a synthetic photocatalyst system that is entirely free of precious metals. We present a series of self-assembled nickel terpyridine complexes as electrocatalysts for the reduction of CO to CO in organic media. Immobilization on CdS quantum dots allows these catalysts to be active in purely aqueous solution and photocatalytically reduce CO with >90% selectivity under UV-filtered simulated solar light irradiation (AM 1.5G, 100 mW cm, λ > 400 nm, pH 6.7, 25 °C). Correlation between catalyst immobilization efficiency and product selectivity shows that anchoring the molecular catalyst on the semiconductor surface is key in controlling the selectivity for CO reduction over H evolution in aqueous solution.
利用光催化剂将 CO 转化为碳质原料化学品是一种很有前途的策略，可以减轻温室气体排放，同时以化学形式储存太阳能。用于这种转化的光催化剂通常基于贵金属，并在非水溶剂中运行，以抑制竞争的 H 生成。在这项工作中，我们使用完全不含贵金属的合成光催化剂系统，在可见光驱动下在水中选择性地还原 CO。我们提出了一系列自组装的镍三联吡啶配合物作为 CO 在有机介质中还原为 CO 的电催化剂。在 CdS 量子点上的固定化使这些催化剂在纯水溶液中具有活性，并在经过紫外线过滤的模拟太阳光照射下（AM 1.5G，100 mW cm，λ>400nm，pH 6.7，25°C）以>90%的选择性光催化还原 CO。催化剂固定化效率与产物选择性之间的相关性表明，将分子催化剂锚定在半导体表面是控制在水溶液中 CO 还原相对于 H 演化选择性的关键。
