利用太阳能和半导体光催化剂把二氧化碳和水转化为高附加值化学品，是解决能源和环境问题的最佳手段之一，但面临转化效率低和产物选择性差等瓶颈问题。针对以上问题，本项目设计并合成介孔C3N4/LDH复合双壳空心微球光催化剂，研究其光催化CO2还原和水氧化反应的活性和产物选择性。一方面，LDH既能增强催化剂对CO2的吸附能力，与C3N4形成的异质结又能促进光生电子和空穴的有效分离；另一方面，将水分解产氧助催化剂CoOx和CO2还原助催化剂CuxO分别构筑在空心球催化剂的内外表面上，使氧化和还原反应位点空间分隔，从而同时进行水氧化反应产生氧气和CO2还原反应生成甲醇等有机产品，实现人工光合作用，并达到提升光催化转化效率和产物选择性的目标。基于以上基础，进一步探索光催化还原CO2反应机制。本项目对研究CO2的资源化利用、光催化材料的发展等问题，具有重要的理论价值。

Use of solar energy and semiconductor photocatalyst to convert carbon dioxide and water into high value-added chemicals, is one of the best way to solve the problem of energy and the environment, but in the face of bottleneck problems such as low efficiency and poor selectivity. To overcome above drawbacks, this project plans to design and synthesize C3N4/LDH mesoporous hollow spheres photocatalyst. The activity and selectivity of photocatalytic CO2 reduction with water oxidation over the nanocomposite will be studied. On the one hand, LDH can enhance CO2 adsorption ability of the catalyst, and also form heterojunction with C3N4 promoting the effective separation of photoexcited electrons and holes; on the other hand, C3N4/LDH double-layered shells are selectively decorated with CoOx nanoparticles as oxidative co-catalysts and CuxO as reductive co-catalysts on the inner and outer surfaces respectively, making the cocatalysts spatially separated. Thus, the reduction of CO2 into chemicals and oxidation of water into oxygen can be promoted simultaneously in the presence of light illumination. The coupling of photocatalytic CO2 reduction with water oxidation to mimic natural photosynthesis also improves the photocatalytic efficiency and selectivity. Based on the above basis, the mechanism of photocatalytic CO2 reduction will be further investigated. This project will be of important theoretical value to study on utilization of CO2 resource and the development of photocatalytic materials.