文献类型：期刊文献

英文题名：Highly active and stable synergistic Ir-IrO2 electro-catalyst for oxygen evolution reaction

作者：Zhou, Zhen-Hua[1];Sun, Wei[1];Zaman, Waqas Qamar[1];Cao, Li-Mei[1];Yang, Ji[1]

机构：[1]East China Univ Sci & Technol, Sch Resources & Environm Engn, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China

年份：2018

卷号：205

期号：7

起止页码：966

外文期刊名：CHEMICAL ENGINEERING COMMUNICATIONS

收录：;EI(收录号：20181204915275);WOS:【SCI-EXPANDED(收录号:WOS:000435526800010)】；

基金：This research is based on work supported by the National Natural Science Foundation of China (Grants 21277045). We thank beamline BL14W1 (Shanghai Synchrotron Radiation Facility) for providing the beam time.

语种：英文

外文关键词：Electrochemical catalyst; hydrogen acceptor; Ir-IrO2 composite; oxygen evolution reaction

摘要：The design of efficient and stable electrocatalysts is still crucial to realize oxygen evolution reaction (OER) in acid and corrosive environment. Inspired by the metal/metal oxides catalysts, we hydrothermally synthesized Ir-IrO2 composites duly confirmed by X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive spectrometer (EDS), X-ray absorption data, and transmission electron microscope results. A low onset over-potential of merely 234 mV and a Tafel slope of 53 mV dec(-1) were obtained for the prepared catalyst Ir-IrO2_0.5AF. In addition, Ir-IrO2_0.5AF catalyst retained high activity for long time under constant potential polarization. The enhanced performance is attributed to the introduction of lower valence Ir as hydrogen acceptor: hydrogen transfers from -OOH intermediate in OER to adjacent H acceptor site, forming intermediate with relatively lower Gibbs free energy, and resulting in higher activity. The present study emphasizes on important role of the lower valence composition in launching H acceptors and providing wide opportunities toward rational designing of efficient and stable electro-catalysts.