Bodappa Nataraju, Su Min, Zhao Yu, Le Jia-Bo, Yang Wei-Min, Radjenovic Petar, Dong Jin-Chao, Cheng Jun, Tian Zhong-Qun, Li Jian-Feng
MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering , Xiamen University , Xiamen 361005 , China.
Department of Physics , Xiamen University , Xiamen 361005 , China.
J Am Chem Soc. 2019 Aug 7;141(31):12192-12196. doi: 10.1021/jacs.9b04638. Epub 2019 Jul 25.
Investigating the chemical nature of the adsorbed intermediate species on well-defined Cu single crystal substrates is crucial in understanding many electrocatalytic reactions. Herein, we systematically study the early stages of electrochemical oxidation of Cu(111) and polycrystalline Cu surfaces in different pH electrolytes using shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS). On Cu(111), for the first time, we identified surface OH species which convert to chemisorbed "O" before forming CuO in alkaline (0.01 M KOH) and neutral (0.1 M NaSO) electrolytes; while at the Cu(poly) surface, we only detected the presence of surface hydroxide. Whereas, in a strongly acidic solution (0.1 M HSO), sulfate replaces the hydroxyl/oxy species. This results improves the understanding of the reaction mechanisms of various electrocatalytic reactions.
研究在明确的铜单晶基底上吸附的中间物种的化学性质对于理解许多电催化反应至关重要。在此，我们使用壳层隔离纳米粒子增强拉曼光谱（SHINERS）系统地研究了不同pH值电解质中Cu(111)和多晶铜表面的电化学氧化早期阶段。在Cu(111)上，我们首次在碱性（0.01 M KOH）和中性（0.1 M NaSO）电解质中识别出在形成CuO之前先转化为化学吸附“O”的表面OH物种；而在Cu（多晶）表面，我们只检测到表面氢氧化物的存在。然而，在强酸性溶液（0.1 M HSO）中，硫酸根取代了羟基/氧物种。这一结果有助于更好地理解各种电催化反应的反应机理。
