缺陷位可控的二维超薄水滑石衍生材料的结构设计及其二氧化碳电催化还原性能研究

Electrochemical reduction of CO2 into small organic molecules is an effective strategy, which can not only reduce the accumulation of CO2 in the atmosphere, but also relieve our dependency on conventional fossil resources. It have significant effects on the development of renewable energy and society. Controllable synthesis of smart electrode materials for electrochemical reduction of CO2 is urgently needed. Besides, the development of Ni-based catalysts with efficient carbon dioxide reduction capability remains a challenge. In this project, it is proposed to synthesis of ultra-thin two-dimensional (2D) layered double hydroxides (LDH), by nitrogen doping techniques to construct its derivatives, which possess abundant defects as active sites and large surface area. It is believed that the catalysis benefits from its 2D ultra-thin structure, highly exposure of defect sites, can reduce the overpotential and suppress HER reaction, make it promising electrode materials for CO2 reduction. The project will systematically investigate the electrochemical behavior of the materials, and explore the relationship between the microstructure and their catalytic performances. The research of this project will provide theoretical guidance for the controllable preparation efficient electrocatalysts for CO2 reduction.

利用电化学方法将二氧化碳转化为可利用的能源小分子，可以有效缓解全球气候变暖、减少人类对化石燃料的依赖，形成可持续的碳基循环，对新能源开发乃至对社会发展均具有重要意义。精准合成具有高反应活性、高选择性及高稳定性的催化剂，是CO2电催化还原技术发展的关键。高效镍基廉价过渡金属CO2电催化还原催化剂的合理设计和构建更是一项挑战。本项目拟以合成具有不同组分的超薄镍基水滑石材料为基础，通过氮掺杂调控表面缺陷位，制备出系列大比表面单原子或少原子层状结构、高缺陷位暴露的镍基氮掺杂/氮化物材料，通过结构和表面缺陷位调控可有效抑制水解产氢反应，降低反应过电位，改善催化剂的二氧化碳电催化还原性能。在此基础上，考察组分、氮掺杂量和掺杂程度等对催化活性的影响和影响机制，探究催化剂结构与活性之间的构效关系，阐明二氧化碳分子在催化剂表面吸附、活化、转化和产物脱附机制。为高效二氧化碳电催化还原催化剂的发展提供理论指导。

由于人类对化石能源的过度消耗，大气中的 CO2 浓度逐渐增加，引起了包括全球气候变暖在内的多种环境问题，威胁全球生态和人类的生存。利用电化学方法将二氧化碳转化为可利用的能源小分子，可以有效缓解全球气候变暖、减少人类对化石燃料的依赖，形成可持续的碳基循环，对新能源开发乃至对社会发展均具有重要意义。本项目通过对反应活性位点的精准调控，合成了系列具有高反应活性、高选择性及高稳定性的催化剂。层状镍基氢氧化/双金属氢氧化物（LDHs）为基础，通过氮掺杂或氮化调控表面缺陷位，制备出系列大比表面单原子或少原子层状结构、高缺陷位暴露的镍基氮掺杂/氮化物材料，通过结构和表面缺陷位调控可有效抑制水解产氢副反应，降低反应过电位，改善催化剂的二氧化碳电催化还原性能。在此基础上，考察了组分、氮掺杂量和掺杂程度等对催化活性的影响和影响机制，探究催化剂结构与活性之间的构效关系，阐明二氧化碳分子在催化剂表面吸附、活化、转化和产物脱附机制。