Discrepant roles of adsorbed OH* species on IrWOx for boosting alkaline hydrogen electrocatalysis

• 作者: Fulin Yang Luhong Fu Shengli Chen Wei Luo Youcheng Hu Yunbo Li
• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2020,（20）
• 所属期刊栏目: ARTICLES
• 页码范围: 1735-1742
• 页数: 8页
• 语种: 英文

摘要

Improving the slow kinetics of alkaline hydrogen electrode reactions,involving hydrogen oxidation and evolution reactions (HOR/HER) is highly desirable for accelerating the commercialization of alkaline exchange membrane-based fuel cells (AEMFCs) and water electrolyzers (AEMWEs).However,fundamental understanding of the mechanism for HOR/HER catalysis under alkaline media is still debatable.Here we develop an amorphous tungsten oxide clusters modified iridium-tungsten nanocrystallines (IrWOx)which exhibited by far the highest exchange current density and mass activity,about three times higher than the commercial Pt/C toward alkaline HOR/HER.Density functional theory (DFT) calculations reveal the WOx clusters act as a pivotal role to boost reversible hydrogen electrode reactions in alkaline condition but via different mechanisms,which are,hydrogen binding energy (HBE) mechanism for HOR and bifunctional mechanism for HER.This work is expected to promote our fundamental understanding about the alkaline HOR/HER catalysis and provide a new avenue for rational design of highly efficient electrocatalysts toward HOR/HER under alkaline electrolytes.