揭示氧化铜在电催化生物质转化中存在的电势依赖的结构演变规律

Unraveling the potential-dependent structure evolution in CuO for electrocatalytic biomass valorization

通过电催化氧化葡萄糖等可再生生物质生产高附加值化学品为实现碳中和目标提供了一条有效途径.目前用于电催化生物质氧化反应的电催化剂主要分为贵金属基催化剂和非贵金属基催化剂.对于贵金属基电催化剂,文献报道了铂基催化剂的氧化态随电势变化,进而调控电催化葡萄糖氧化的活性和选择性.对于非贵金属基催化剂,钴基和镍基氧化物和氢氧化物被广泛应用于电催化生物质氧化反应,但铜基催化剂直到最近才引起关注.最近,金属铜、氧化亚铜和氢氧化铜在内的铜基材料被证实是一类有应用前景的电催化生物质氧化催化剂,但在电化学条件下的真实活性位结构仍难以鉴定.本文针对电催化葡萄糖等生物质平台分子的氧化反应,证明了氧化铜的催化活性相随电压升高从氢氧化铜演变为羟基氧化铜,阐明了结构和反应活性及选择性的构效关系,该工作加深了对铜基催化剂活性位动态重构的理解,有助于电催化生物质转化的催化剂理性设计,促进可再生资源利用和碳中和目标的实现.

Electrocatalytic oxidation of renewable biomass(such as glucose)into high-value-added chemicals provides an effective approach to achieving carbon neutrality.CuO-derived materials are among the most promising electrocatalysts for biomass electrooxidation,but the identification of their active sites under electrochemical conditions remains elusive.Herein,we report a potential-dependent structure evolution over CuO in the glucose oxidation reaction(GOR).Through systematic electrochemical and spectroscopic characterizations,we unveil that CuO undergoes Cu^(2+)/Cu^(+) and Cu^(3+)/Cu^(2+)redox processes at increased potentials with successive generation of Cu(OH)_(2) and CuOOH as the active phases.In addition,these two structures have distinct activities in the GOR,with Cu(OH)_(2) being favorable for aldehyde oxidation,and CuOOH showed faster kinetics in carbon–carbon cleavage and alcohol/aldehyde oxidation.This work deepens our understanding of the dynamic reconstruction of Cu-based catalysts under electrochemical conditions and may guide rational material design for biomass valorization.