基于碳基量子点的多组分高效CO2还原光催化剂体系设计

The photocatalytic reduction of CO2 to produce fuel or high value-added chemicals is one of the ideal strategies to solve the energy crisis. At the same time, it can effectively reduce the content of CO2 in the environment and reduce the adverse environmental impact caused by the greenhouse effect. The adsorption and activation of CO2 is a key step in its reduction, and the existing catalyst is easily deactivated. This project aims to combine the catalytic properties of carbon-based quantum dots (high stability, fast electron conduction, large specific surface area, strong light absorption characteristics, etc.) and the advantages of narrow bandgap semiconductors in terms of catalysis (easy to be excited by visible light, simple synthesis, etc.) Design and construction of multi-component high-efficiency CO2 photocatalysts based on carbon-based quantum dots. The system adjusts the structure of the carbon-based quantum dots and the dimensions and size of the semiconductor nanomaterials, improves the electron transfer ability between the composite systems, and achieves the control of the catalytic activity of the composite photocatalytic system, improve the stability. Investigate the reaction mechanism of the composite photocatalytic system in the reduction reaction. Further, by means of doping and surface modification and the like, the electron conduction speed is improved, and the electron conduction performance is enhanced, so as to increase the catalytic activity of the catalyst and obtain an efficient composite photocatalyst.

光催化CO2还原产生燃料或者高附加值化学品是解决能源危机的理想策略之一，同时又能有效的降低环境中的CO2含量，减轻由其导致的温室效应对环境的不利影响。CO2的吸附和活化是其被还原的关键步骤，同时现有的催化剂易失活。本项目旨在结合碳基量子点的催化特性（高稳定性，快的电子传输，高比表面积，强的光吸收特性等）和窄带隙半导体在催化方面的优势（易被可见光激发，合成简单等），设计构筑基于碳基量子点的多组分高效CO2光催化剂体系。系统的调节碳基量子点的结构和半导体纳米材料的尺寸和维度，提升复合体系组分间电子传输能力，实现对复合光催化体系催化性能的调 控，增强稳定性。研究复合光催化体系在还原反应中的反应机理。进一步通过掺杂和表面修饰等手段，提高电子传导速度，增强体系电子传导性能等，来提高催化剂的催化活性，进一步开发高效的复合光催化剂。

通过本项目的实施，获得了多种碳基量子点/窄带隙半导体纳米复合催化材料，将其作为光催化剂可以实现高效的二氧化碳还原合成高附加值化学品。通过探索碳基量子点与窄带隙半导体纳米材料的结合方式、组分、维度尺寸等对复合体系催化性能的影响，优化了复合催化体系的结构和催化性能。初步了解了复合催化体系在二氧化碳光催化还原反应中的反应机理。此外，拓展了所获得碳基量子点/窄带隙半导体纳米复合催化体系的光电性能，在温和条件下，实现了高效的光催化或电催化合成氨。所获得的这些相关结论及经验，无论是对能源环境问题，还是对复合体系表界面研究都具有重要的理论及实践意义。