解析带间和带内跃迁激发热空穴对光增强电催化乙醇氧化的贡献  

Distinguishing the contributions of hot holes from interband and intraband transitions to the photoenhanced electrocatalytic oxidation reaction of ethanol

作　　者：迟晨 倪淼 丁新雷 杨冬蕊 李剑 夏兴华 Chen Chi;Miao Ni;Xin-Lei Ding;Dong-Rui Yang;Jian Li;Xing-Hua Xia(State Key Laboratory of Analytical Chemistry for Life Science,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing 210023,China)

机构地区：[1]State Key Laboratory of Analytical Chemistry for Life Science,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing 210023,China

出　　处：《Science Bulletin》2023年第5期477-480,M0003,共5页科学通报（英文版）

基　　金：supported by the National Key Research and Development Program of China(2017YFA0206500);the National Natural Science Foundation of China(21635004,22004069,and 22227806);the Excellent Research Program of Nanjing University(ZYJH004).

摘　　要：等离激元共振产生的高能热载流子可以降低反应能垒,加速特定的电化学反应.然而,绝大多数研究聚焦于热电子的高效利用,对于热空穴,特别是带间激发的热空穴在光增强电氧化反应(PEEO)中的作用尚缺乏研究.本文以金纳米三角结构作为电催化剂,解析了带间和带内跃迁激发的热空穴对电催化乙醇氧化反应的贡献.研究发现,尽管带内跃迁的消光截面是带间跃迁的5倍,但由于d带热空穴具有更高的氧化电势,带间激发对电催化乙醇氧化反应过程具有更高的催化活性,展示出更高的电流密度和更低的起峰电势.根据光照前后电化学反应活化能和起峰电位,进一步建立了估算PEEO中热空穴贡献的方法.定量分析结果表明,带间激发热空穴的相对光电化学转换效率比带内激发高12倍,证明d带热空穴在PEEO中具有更高的反应活性.本工作不仅揭示了PEEO中热空穴的详细作用机制,且对于高效设计等离激元共振电催化剂有重要意义.The localized surface plasmon resonance(LSPR)of plasmonic nanomaterials provides a unique way to harvest and convert light energy.During LSPR excitation(intraband transition),hot electrons within the sp bands are excited to energy levels much higher than the Fermi level,leaving holes in the deep sp bands[1].The energy of the hot electron-hole pair transfers to the adsorbate or directly mediates chemical reactions by reducing the energy barrier.

关 键 词：乙醇氧化 电催化 等离激元共振 电化学反应 光电化学 三角结构 热载流子 带间跃迁 

分 类 号：O643.36[理学—物理化学]