曲率诱导的碳曲面缺陷结构调控及其二氧化碳电还原机理研究

缺陷的微观结构调控及其电催化机理的阐释对优化和提升缺陷纳米碳催化材料的CO2电还原性能至关重要，但是目前已有研究主要集中在平面碳层上缺陷结构的设计，而对曲面碳层体系中缺陷的构建与调控及其与CO2电还原性能之间的构效关系尚不清楚。针对这一问题，本项目拟在曲率梯度变化的碳纳米管上构建过渡金属掺杂缺陷和本征缺陷，探究曲率调变诱导的曲面张力变化对缺陷微观结构和电子结构的调控作用，实现基于碳曲面构型的高效CO2电还原催化剂的构筑。在此基础上，深入研究缺陷的形成过程和曲率影响缺陷微观结构的机制；探究曲率对缺陷电子结构的影响规律；利用原位表征和理论模拟等手段揭示曲率与CO2及中间物种的吸附构型和吉布斯自由能变的相互关系，阐明曲率调控碳曲面内缺陷催化CO2电还原性能的机制。本项目的实施将为纳米碳材料缺陷结构可控制备提供新的思路，对推进缺陷纳米碳材料在电催化领域中的理论与应用研究具有重要意义。

It is critical to adjust the defect microstructure and to clarify its electrocatalytic mechanism for improving the performance of CO2 electrochemical reduction (CO2RR) of defective nano-carbon materials. However, current researches mainly focus on the design of defect structures on the carbon plane. For curved carbon surface, the construction and regulation of defect structure and its structure-activity relationship with CO2RR are still unclear. In response to this problem, this project intends to construct transition metal doping defects and intrinsic defects on carbon nanotubes with gradient changes in curvature. Curvature modulation induces surface tension change, and synchronously controls the defect microstructure and electronic structure to achieve a highly active electrocatalyst for CO2RR based on the curved carbon surface. Further researches about the formation process of defects and the mechanism of curvature regulating the microstructure of defects are conducted. The influence of curvature on the electronic structure of defects is also explored. The relationships between the curvature and the adsorption configuration of CO2 and its reduction intermediates as well as the Gibbs free energy change are revealed by in-situ characterization and theoretical simulation. Finally, we clarify the mechanism that the curvature regulates the catalytic ability of defects for CO2RR. This project will provide a new idea for the controllable construction of defective carbon nanomaterials. It is of great significance to promote the theoretical and applied research of defective carbon nanomaterials in the field of electrocatalysis.