Kuznetsov Denis A, Naeem Muhammad A, Kumar Priyank V, Abdala Paula M, Fedorov Alexey, Müller Christoph R
Department of Mechanical and Process Engineering, ETH Zürich, CH 8092 Zürich, Switzerland.
School of Chemical Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia.
J Am Chem Soc. 2020 Apr 29;142(17):7883-7888. doi: 10.1021/jacs.0c01135. Epub 2020 Apr 6.
Ruthenium pyrochlores, that is, oxides of composition ARuO, have emerged recently as state-of-the-art catalysts for the oxygen evolution reaction (OER) in acidic conditions. Here, we demonstrate that the A-site substituent in yttrium ruthenium pyrochlores YMRuO (M = Cu, Co, Ni, Fe, Y) controls the concentration of surface oxygen vacancies (V) in these materials whereby an increased concentration of V sites correlates with a superior OER activity. DFT calculations rationalize these experimental trends demonstrating that the higher OER activity and V surface density originate from a weakened strength of the M-O bond, scaling with the formation enthalpy of the respective MO phases and the coupling between the M states and O 2 states. Our work introduces a novel catalyst with improved OER performance, YCuRuO, and provides general guidelines for the design of active electrocatalysts.
钌烧绿石，即组成为ARuO的氧化物，最近已成为酸性条件下析氧反应（OER）的先进催化剂。在此，我们证明钇钌烧绿石YMRuO（M = Cu、Co、Ni、Fe、Y）中的A位取代基控制着这些材料中表面氧空位（V）的浓度，由此V位浓度的增加与优异的OER活性相关。密度泛函理论（DFT）计算使这些实验趋势合理化，表明较高的OER活性和V表面密度源于M - O键强度的减弱，与相应MO相的形成焓以及M态与O 2态之间的耦合成比例。我们的工作引入了一种具有改进OER性能的新型催化剂YCuRuO，并为活性电催化剂的设计提供了通用指导方针。
