摘要
Electroreduction derived Cu-based two-dimensional materials have emerged as promising catalysts for the electroreduction of CO_(2)to C_(2+)products;however,it remains ambiguous whether the reconstructed interface structures significantly impact the reduction performance.Herein,we first fabricate interface-engineered Cu nanosheets via in situ pre-electrolysis of kilogram-scale brochantite nanosheets precursors,in which lead underpotential deposition reveals the presence of abundant Cu(100)/Cu(110)interfaces,confirmed by OH−electrosorption analysis.In situ attenuated total reflection-surface enhanced infrared absorption spectroscopy elucidates the C-C coupling pathways involving the hydrogenation of*CO intermediates to form*CHO species,followed by their subsequent coupling to generate*COCHO.Operando Raman spectra demonstrate that the abundant interfaces provide sufficient*CO surface coverage,thereby facilitating the subsequent deep coupling reactions.Moreover,density-functional-theory calculations indicate the Cu(100)/Cu(110)interfaces reduce the energy barriers of rate-determining hydrogenation step by 0.16 eV and promote the coupling of*CO and*CHO.As a result,the Cu nanosheets with rich Cu(100)/Cu(110)interfaces achieve a remarkable C_(2+)Faradaic efficiency of 80.4%at a current density of 800 mA cm^(−2),surpassing most reported Cu-based catalysts.
电还原衍生的Cu基二维材料因其优异的电还原CO_(2)-C_(2+)转化性能备受关注,但重建的界面结构对催化性能影响仍不清楚.在此,我们首先通过原位预还原方法制备了铜纳米片,并且利用铅欠电位沉积与OH-电吸附实验揭示了其存在丰富的Cu(100)/Cu(110)界面.原位衰减全反射-表面增强红外吸收光谱阐明了C-C偶联途径,包括*CO中间体氢化形成*CHO,随后与另一个*CO偶联生成*COCHO.进一步地,原位拉曼光谱证实丰富的Cu(100)/Cu(110)界面提供了充足的*CO表面覆盖度,从而促进了后续的C-C偶联反应.此外,密度泛函理论计算结果证实,Cu(100)/Cu(110)界面大幅降低了*CO氢化的能垒,促进了*CO和*CHO的偶联反应.基于上述结果,具有丰富Cu(100)/Cu(110)界面的Cu纳米片在800 mA cm^(-2)时表现出高达80.4%的C_(2+)法拉第效率,优于大多数已报道的Cu基催化剂.
基金
supported by the National Natural Science Foundation of China(22125503,52394201,224B2511)
China Postdoctoral Science Foundation(BX20240358).
