Restructuring and Activation of Cu(111) under Electrocatalytic Reduction Conditions
Restructuring and Activation of Cu(111) under Electrocatalytic Reduction Conditions
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DOI：
10.1002/anie.202218575
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发表时间：
2023-04-05
影响因子：
16.6
通讯作者：
Sautet, Philippe
中科院分区：
文献类型：
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作者：
Cheng, Dongfang;Wei, Ziyang;Sautet, Philippe
电还原条件下铜表面的动态重构是电催化领域的研究热点。结合第一性原理计算和电化学扫描隧道显微镜(ECSTM)实验，对还原条件下铜(111)电极的结构动力学进行了研究。结合全局优化和宏正则密度泛函理论，我们揭示了酸性电解液中铜(111)的电势和pH相关的重排过程。在还原电势下，铜(111)面被高密度的氢原子覆盖，在阈值电势以下，铜原子以(4×4)的超结构形式在表面形成，这在真空中是不利于结构重组的。氢的强吸附是重组的驱动力，其本身是由电极电位引起的。在重构的表面上，析氢反应步骤的势垒较低。在电还原条件下的重组产生了不存在于铜(111)上的高活性铜吸附原子位置。
The dynamic restructuring of Cu surfaces in electroreduction conditions is of fundamental interest in electrocatalysis. We decode the structural dynamics of a Cu(111) electrode under reduction conditions by joint first-principles calculations and operando electrochemical scanning tunneling microscopy (ECSTM) experiments. Combining global optimization and grand canonical density functional theory, we unravel the potential- and pH-dependent restructuring of Cu(111) in acidic electrolyte. At reductive potential, Cu(111) is covered by a high density of H atoms and, below a threshold potential, Cu adatoms are formed on the surface in a (4x4) superstructure, a restructuring unfavorable in vacuum. The strong H adsorption is the driving force for the restructuring, itself induced by the electrode potential. On the restructured surface, barriers for hydrogen evolution reaction steps are low. Restructuring in electroreduction conditions creates highly active Cu adatom sites not present on Cu(111).