Abeyweera Sasitha C, Yu Jie, Perdew John P, Yan Qimin, Sun Yugang
Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States.
Department of Physics, Temple University, 1925 North 12th Street, Philadelphia, Pennsylvania 19122, United States.
Nano Lett. 2020 Apr 8;20(4):2806-2811. doi: 10.1021/acs.nanolett.0c00518. Epub 2020 Mar 24.
Silver nanostructures with hierarchical porosities of multiple length scales have been synthesized through electrochemical reduction of silver benzenethiolate nanoboxes. The porous Ag nanostructures exhibit superior catalytic performance toward electrochemical reduction of CO. The Faradaic efficiency of reducing CO to CO can be close to 100% at high cathodic potentials, benefiting from the readsorbed benzenethiolate ions on the Ag surface that can suppress the hydrogen evolution reaction (HER). Density functional theory calculations using the SCAN functional reveal that the disfavored H binding on the benzenethiolate-modified Ag surface is responsible for inhibiting the HER. The mass-specific activity of CO reduction can be over 500 A/g because the multiple-scale porosities maximize the diffusion of reactive species to and away from the Ag surface. The unique multiscale porosities and surface modification of the as-synthesized Ag nanostructures make them a class of promising catalysts for electrochemical reduction of CO in protic electrolytes to achieve maximum activity and selectivity.
通过电化学还原苯硫醇银纳米盒合成了具有多个长度尺度分级孔隙率的银纳米结构。多孔银纳米结构对一氧化碳的电化学还原表现出优异的催化性能。在高阴极电位下，将一氧化碳还原为一氧化碳的法拉第效率可接近100%，这得益于银表面重新吸附的苯硫醇盐离子能够抑制析氢反应（HER）。使用SCAN泛函的密度泛函理论计算表明，苯硫醇盐修饰的银表面上不利的氢结合是抑制析氢反应的原因。一氧化碳还原的质量比活性可以超过500 A/g，因为多尺度孔隙率使反应物种向银表面扩散以及从银表面扩散离开的过程最大化。所合成的银纳米结构独特的多尺度孔隙率和表面修饰使其成为一类有前景的催化剂，用于在质子电解质中电化学还原一氧化碳以实现最大活性和选择性。
