XAFS study on structure-activity correlations of α-Co(OH)2 nanosheets water oxidation catalysts

16th International Conference on X-ray Absorption Fine Structure

Huang, Junheng^1 ; Liu, Qinghua^1 ; Yao, Tao^1 ; Pan, Zhiyun^1 ; Wei, Shiqiang^1

National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui

230029, China^1

关键词: Exposed surfaces;    In-situ formations;    Oxygen evolution reaction;    Structural evolution;    Structure activity;    Structure activity correlations;    Surface active sites;    Water oxidation catalysts;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/712/1/012128/pdf
DOI  :  10.1088/1742-6596/712/1/012128

来源: IOP

【 摘 要 】

Understanding the structure-activity of the metal hydroxide materials is critical to the design of an efficient oxygen evolution reaction (OER) catalyst for water oxidation. A challenge is to identify and collect surface active site relative to bulk. Here, we have prepared an ultrathin α-Co(OH)2nanosheet with large exposed surface Co sites as an high-efficiency O2evolution catalyst. Using XAFS technique, we have investigated the oxidation state and local structural evolutions of the α-Co(OH)2nanosheets catalyst. A coordination-miss Co sites (CoO6-x) with oxidation state of +3.3 on the nanosheet surface is revealed after the OER procedure, indicating the in situ formation of y-CoOOH nanosheet is a key factor leading to an enhanced water oxidation performance.