超薄Cu2O肖特基结[M/Cu2O，M=(Pt, Pd, Au)]的构筑及其界面调控对电催化还原CO2性能研究

Electrochemical CO2 reduction (ECR) is an effective means of alleviating energy crises and reducing global carbon content. Cu2O-based electrocatalyst can efficiently convert CO2 into C2+ product with high energy density, but so far there are still some problems such as poor stability and unclear surface reaction mechanism. Herein, based on the previous research, this project aims to design and synthesize a class of simple and stable ultrathin Cu2O-based electrocatalyst with Schottky junction structure [M/Cu2O，M=(Pt, Pd, Au)] by using photo-deposition and ultrasonic self-assembly methods. The Schottky junction interface is optimized by controlling the crystal surface and particle size of metal M on ultrathin Cu2O nanosheets, which will improve the stability of the Cu2O-based catalyst during the ECR reaction and achieve high conversion efficiency of CO2. Meanwhile, the intrinsic relationship between Schottky junction interface and catalyst stability and product selectivity is revealed. In addition, combined with in-situ infrared spectroscopy and density functional theory calculation, the reaction mechanism on the catalyst surface is elucidated from the atomic scale. The completion of the project will promote the in-depth study of Cu2O-based catalysts in ECR system and provide experimental data and theoretical guidance for the further design and development of novel catalysts with high ECR performance .

电化学还原CO2（ECR）是缓解能源危机和降低全球碳含量的一种有效手段。其中，氧化亚铜（Cu2O）类催化剂能高效催化CO2转化为高热值C2+产物，但迄今依然面临稳定性差及反应机理研究复杂等问题。本项目在前期研究基础上拟通过光沉积和超声自组装的方法构建一类结构简单且稳定的超薄Cu2O肖特基结催化剂[M/Cu2O，M=(Pt, Pd, Au)]。通过调控金属M纳米晶的晶面及尺寸，优化肖特基结界面，提高Cu2O基催化剂在ECR体系中的稳定性，实现对电催化CO2的高效转化，揭示肖特基结界面和界面大小与催化剂稳定性以及ECR产物选择性的内在关系。进而结合原位红外光谱等表征技术和密度泛函理论计算从原子尺度上阐明该催化剂表面反应机理。该项目的实施，将促进Cu2O基催化剂在ECR体系中的深入研究，并为进一步设计和开发高性能的新型ECR催化剂提供实验数据和理论指导。

电化学CO2还原（ECR）过程可将CO2在温和条件下转化为高附加值化学品。但是，该过程依然面临反应过电位较高、动力学过程缓慢、催化剂稳定性较差等问题。基于此，本课题主要围绕铜基氧/硫化物催化剂的精准合成（如Cu2O肖特基结/异质结催化剂，多晶界Cu2S Janus结构催化剂）展开，深入研究了肖特基结/异质结界面大小、Janus晶界含量、Cu空位浓度对其电化学性能的影响，建立了构效关系。这些结果对于合成高性能电催化剂具有一定指导意义。项目执行期间取得的研究成果主要包括以下两方面：（1）系统研究了Cu基氧/硫化物催化剂结构改变对其ECR产物分布的影响，实现了CO2还原产物定向高效转化（如乙醇、合成气）的催化剂开发，同时借助异质结/肖特基结的构筑有效提升了Cu基氧/硫化物催化剂的稳定性。（2）聚焦CO2还原对电极表面析氧反应，设计了几类高活性光/电阳极材料，有效降低了析氧过电位，提升了CO2还原反应电解槽效率。研究结果为Cu基氧/硫化物催化剂ECR性能研究提供了实验依据和理论指导。本项目完成了计划书上规定任务及预期目标。