Zheng, JieSheng, WenchaoZhuang, ZhongbinXu, BingjunYan, Yushan2017-04-072017-04-07Copyright2016-01-14Zheng, Jie, et al. "Universal dependence of hydrogen oxidation and evolution reaction activity of platinum-group metals on pH and hydrogen binding energy." Science advances 2.3 (2016): e1501602.3- 2375-2548http://udspace.udel.edu/handle/19716/21218Publisher's PDFUnderstanding how pH affects the activity of hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) is key to developing active, stable, and affordable HOR/HER catalysts for hydroxide exchange membrane fuel cells and electrolyzers. A common linear correlation between hydrogen binding energy (HBE) and pH is observed for four supported platinum-group metal catalysts (Pt/C, Ir/C, Pd/C, and Rh/C) over a broad pH range (0 to 13), suggesting that the pH dependence of HBE is metal-independent. A universal correlation between exchange current density and HBE is also observed on the four metals, indicating that they may share the same elementary steps and rate-determining steps and that the HBE is the dominant descriptor for HOR/HER activities. The onset potential of CO stripping on the four metals decreases with pH, indicating a stronger OH adsorption, which provides evidence against the promoting effect of adsorbed OH on HOR/HER.en-USCreative Commons Attribution-NonCommercial 4.0 International (CC BY- NC 4.0)Articlehttps://doi.org/10.1126/sciadv.1501602