具有氧空位的In2O3/In2S3异质结光催化剂的设计合成及其可见光催化固氮性能研究

以太阳能驱动的光催化固氮制氨技术是新型绿色清洁的人工固氮方法之一，如何有效地活化N2分子和提高催化剂的量子效率是光催化固氮技术急需解决的关键科学问题。本项目拟以氧空位作为N2分子的吸附和活化位点和In2O3材料为异质结光催化剂中的主体材料，通过简易可控的阴离子交换法在In2O3上原位构筑具有氧空位的In2O3/In2S3异质结可见光催化剂，阐明异质结形成机理及构建过程的结构优化机制，获得光催化性能稳定的In2O3/In2S3异质结的制备方法；期待在实现较高N2分子活化能力的同时，设计合成出具有较高可见光光催化效率的新型异质结光催化剂，并考察其利用太阳能光催化固氮的性能；探明异质结的结构组成、表面氧空位的浓度、禁带宽度的降低对光催化固氮性能的协同作用机制，建立明确的构效关系；揭示In2O3/In2S3异质结可见光催化固氮反应机理。该研究为开发高效低耗的光催化固氮制氨技术及其实际应用奠定基础。

Solar-driven photocatalytic fixation of nitrogen to ammonia is a novel green and clean strategy for artificial nitrogen fixation. The efficiency of photocatalytic N2 fixation highly depends on the catalytic activation center capable of activating the N-N triple bond and photocatalytic performance of catalysts. In this project, we propose to construct In2O3/In2S3 heterojunction photocatalysts with oxygen vacancies (OVs) as the catalytic activation centers and In2O3 as the base material. We will synthesize the In2O3/In2S3 heterojunction photocatalysts with OVs based on as-prepared In2O3 via a facile and controllable hydrothermal process followed by an in situ anion exchange reaction. The formation mechanism and the optimization of formation conditions will be investigated, and the optimized fabrication method of the In2O3/In2S3 heterojunctions with stable photocatalytic performance will be achieved，and its performance in Solar-driven photocatalytic fixation of nitrogen to ammonia will be further investigated. The design and fabrication of novel heterojunction photocatalysts with the improved visible-light-driven photocatalytic efficiency as well the better ability to activate N2 will be envisaged. The well-defined structure-activity relationship of the heterojunction photocatalysts will be built by investigating the synergistic effect of the composition and structure of catalysts, the concentration of OVs, and the reduction of heterojunction’s bandgap on the performance of photocatalytic N2 fixation. The mechanism of visible-light-driven photocatalytic N2 fixation will be clarified. The outcomes of this project will greatly contribute to the development of the efficient and low energy-consuming photocatalytic N2 fixation technique and the practical application.