Wang Zhiyuan, Yang Jia, Cao Junbo, Chen Wenxing, Wang Gang, Liao Fan, Zhou Xiao, Zhou Fangyao, Li Ruilong, Yu Zhen-Qiang, Zhang Guoqing, Duan Xuezhi, Wu Yuen
School of Chemistry and Materials Science, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China.
School of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China.
ACS Nano. 2020 May 26;14(5):6164-6172. doi: 10.1021/acsnano.0c02162. Epub 2020 May 11.
Developing a convenient and effective method to prepare single-atom catalysts at mild synthetic conditions remains a challenging task. Herein, a voltage-gauged electrofiltration method was demonstrated to synthesize single-atom site catalysts at room temperature. Under regulation of the graphene oxide membrane, a bulk Fe plate was directly converted into Fe single atoms, and the diffusion rate of Fe ions was greatly reduced, resulting in an ultralow concentration of Fe around the working electrode, which successfully prevented the growing of nuclei and aggregating of metal atoms. Monatomic Fe atoms are homogeneously anchored on the as-prepared nitrogen-doped carbon. Owing to the fast photoelectron injection from photosensitizers to atomically dispersed Fe sites through the highly conductive supported N-C, the Fe-SAs/N-C exhibits an outstanding photocatalytic activity toward CO aqueous reduction into syngas with a tunable CO/H ratio under visible light irradiation. The gas evolution rates for CO and H are 4500 and 4950 μmol g h, respectively, and the tunable CO/H ratio is from 0.3 to 8.8. This article presents an efficient strategy to develop the single-atom site catalysts and bridges the gap between heterogeneous and homogeneous catalysts toward photocatalytic CO aqueous reduction into syngas.
开发一种在温和合成条件下制备单原子催化剂的便捷有效方法仍然是一项具有挑战性的任务。在此，展示了一种电压测量电过滤方法，可在室温下合成单原子位点催化剂。在氧化石墨烯膜的调控下，块状铁板直接转化为铁单原子，铁离子的扩散速率大大降低，导致工作电极周围铁的浓度超低，成功防止了核的生长和金属原子的聚集。单原子铁原子均匀地锚定在制备的氮掺杂碳上。由于通过高导电性负载的氮碳从光敏剂到原子分散的铁位点的快速光电子注入，Fe-SAs/N-C在可见光照射下对CO水溶液还原为合成气表现出优异的光催化活性，CO/H比可调。CO和H的析气速率分别为4500和4950 μmol g h，可调的CO/H比为0.3至8.8。本文提出了一种开发单原子位点催化剂的有效策略，并弥合了多相催化剂和均相催化剂在光催化CO水溶液还原为合成气方面的差距。
