Zhou Baowen, Ou Pengfei, Pant Nick, Cheng Shaobo, Vanka Srinivas, Chu Sheng, Rashid Roksana Tonny, Botton Gianluigi, Song Jun, Mi Zetian
Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109.
Department of Electrical and Computer Engineering, McGill University, Montreal, QC H3A0E9, Canada.
Proc Natl Acad Sci U S A. 2020 Jan 21;117(3):1330-1338. doi: 10.1073/pnas.1911159117. Epub 2020 Jan 3.
A rational design of an electrocatalyst presents a promising avenue for solar fuels synthesis from carbon dioxide (CO) fixation but is extremely challenging. Herein, we use density functional theory calculations to study an inexpensive binary copper-iron catalyst for photoelectrochemical CO reduction toward methane. The calculations of reaction energetics suggest that Cu and Fe in the binary system can work in synergy to significantly deform the linear configuration of CO and reduce the high energy barrier by stabilizing the reaction intermediates, thus spontaneously favoring CO activation and conversion for methane synthesis. Experimentally, the designed CuFe catalyst exhibits a high current density of -38.3 mA⋅cm using industry-ready silicon photoelectrodes with an impressive methane Faradaic efficiency of up to 51%, leading to a distinct turnover frequency of 2,176 h under air mass 1.5 global (AM 1.5G) one-sun illumination.
合理设计电催化剂为通过二氧化碳（CO）固定合成太阳能燃料提供了一条有前景的途径，但极具挑战性。在此，我们使用密度泛函理论计算来研究一种用于光电化学CO还原制甲烷的廉价二元铜铁催化剂。反应能量学计算表明，二元体系中的Cu和Fe可以协同作用，显著使CO的线性构型变形，并通过稳定反应中间体来降低高能垒，从而自发地促进CO活化和转化以合成甲烷。实验上，使用工业现成的硅光电极时，所设计的CuFe催化剂表现出-38.3 mA⋅cm的高电流密度，甲烷法拉第效率高达51%，在空气质量1.5全球（AM 1.5G）标准阳光照射下，其周转频率高达2176 h⁻¹。
