基于钛基类石墨烯结构的CO2光热还原催化剂的设计和制备

CO2 reduction is considered to be one of the best strategies to reduce carbon dioxide emissions and to solve the greenhouse effect. At present, CO2 reduction photocatalysts and thermalcatalysts are widely investigated. However, CO2 reduction photocatalyst has the problems of low activity and low utilization of solar energy. While CO2 reduction thermalcatalysts usually need ultrahigh reaction temperature and hydrogen, hindering the practical application. Therefore, CO2 reduction photothermalcatalysts are of important research value. They can not only improve the activity of CO2 by external heating, but also decrease the temperature needed by thermal reaction by adding solar light irradiation, and so as to synergistic enhance the performance of CO2 reduction. This project focuses on the application of solar photothermal CO2 reduction. Taking Titanium-based graphene-analogue structure semiconductors as the research object, the advanced characterization technology such as extended X-ray absorption fine structure (EXAFS), high-resolution angle-resolved photoemission spectroscopy(HR-SRPES), surface photovoltage(SPV) and synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS), followed with density functional theory(DFT) calculations, will be adopted to study the relationship between micro-structure and macro-properties, hence optimizing the reaction process. Therefore, through this project, titanium-based graphene-analogue structure with photothermal reduction of CO2 properties will be obtained, and the relationship between the structure of graphene-analogue structure and the property of photothermal reduction of CO2 will be elucidated.

二氧化碳(CO2)催化还原制碳基燃料被认为是减少CO2排放和解决温室效应的最佳策略之一，然而单一的光还原CO2反应存在活性低、选择性差等问题，而单一的热还原CO2则通常需要高温和氢气，反应条件苛刻，阻碍它们在实际生产中的应用。因此，光热催化还原CO2具有重要研究价值，它既可以外加热源提高光还原CO2的活性，也可以通过加光弥补热催化需要的高温，从而达到协同提升CO2还原性能的目的。基于此，本项目将聚焦光热还原CO2应用，以钛基类石墨烯材料为研究对象，利用X射线吸收精细结构谱(EXAFS)、同步辐射光电子能谱(HR-SRPES)、表面光电压谱(SPV)以及同步辐射光电离质谱(SVUV-PIMS)等先进表征手段，结合密度泛函理论计算，研究原子结构、电子结构与宏观性能的内在关系。通过本项目的实施，将获得具有光热还原CO2性能的钛基类石墨烯催化剂，阐明类石墨烯结构与光热还原CO2性能之间的构效关系。

二氧化碳(CO2)催化还原制碳基燃料被认为是减少CO2排放和解决温室效应的最佳策略之一，光还原CO2反应存在活性低、选择性差等问题，而热还原CO2则通常反应条件苛刻。针对目前的光/热催化难点，本项目设计构建了可实现CO2捕捉和活化的钛基类石墨烯催化剂，并且利用正电子湮没寿命谱、同步辐射光电子能谱(HR-SRPES)、同步辐射光电离质谱(SVUV-PIMS)以及密度泛函理论计算清晰阐明了微观缺陷结构与CO2还原之间的构效关系。同时，我们还将相应研究拓展至对热效应极为敏感的红外光催化体系，利用超快光谱和发光光谱技术，并结合理论模拟研究了该类材料中红外光激发的电子经历了连续的带内弛豫和带间复合过程，为实现高效的红外光驱动CO2减排性能提供更深层次的理解。