基于卤素促进钼酸铋钼中心的光诱导价变行为及其光催化固氮研究

Efficient photocatalyst for nitrogen fixation is an emerging energy conversion material, which has attracted much attention for its potential to solve energy shortage and environment pollution. Biomimetic fabrication of low valence Molybdenum (Mo) -based photocatalyst is a pivotal strategy to enhance the activity of nitrogen reduction. However, the consumption of low valence Mo during the photocatalytic reaction largely decreased the efficiency of nitrogen reduction. Therefore, it is crucial to fabricate the variable valence of Mo Center during the photocatalytic reaction, but such researches are very limited and the mechanism of valence change circulation of Mo-based catalysts is still unknown. In this project, the effect of halogen on photo-induced variable valence behavior of Mo center on Bismuth Molybdate during the photocatalytic nitrogen reduction will be systematically studied. In specifically, the halogen affects the formation of low-valence molybdenum center and the photo-induced variable valence of molybdenum will be investigated via theoretical simulation and in-situ characterization. The mechanism of photo-induced variable valence behavior of molybdenum center and its promotion for photocatalytic nitrogen fixation will be revealed by using conditional control and products analysis method. Utilizing the light-induced variable valence behavior of molybdenum center to realize high-efficiency and stable photocatalytic nitrogen fixation and to establish a strategy for designing high-efficiency photocatalytic nitrogen fixation materials.

高效光催化固氮材料作为一类新型的能量转换材料，因其具有解决能源与环境双重危机的巨大潜力而备受关注。依据仿生学原理构筑低价钼活性中心实现氮气的还原是当前设计光催化固氮材料的重要策略之一，但低价钼在催化过程中的损耗严重影响了光催化固氮反应的效率。因此，构建金属钼中心的价变循环行为对光催化固氮反应具有重要意义，然而相关研究尚不多见，变价金属钼中心的调控机制更是鲜有报道。本项目拟选取含卤素的钼酸铋材料为研究对象，系统研究卤素促进钼酸铋钼中心的光诱导价变行为机制及其对光催化固氮反应的作用。通过理论模拟及原位表征考察卤素促进低价钼中心形成能的变化，探究光诱导钼中心价变行为的影响因素；利用条件控制及产物分析研究钼酸铋钼中心光诱导价变行为的机理，揭示其对光催化固氮反应的增效机制；探索出利用钼酸铋钼中心的光诱导价变行为实现高效、稳定光催化固氮反应，以期建立基于变价金属中心设计高效光催化固氮材料的策略体系。

构建金属中心的价变循环行为对光催化固氮反应具有重要意义，然而相关研究尚不多见，变价金属钼中心的调控机制更是鲜有报道。本项目在项目执行内根据申报书研究计划有序进行，完成了项目预设定的研究内容：1）卤素影响钼酸铋低价金属中心形成能变化及含卤素钼酸铋的合成研究；2）光诱导的钼酸铋金属中心变价行为调控及其行为机制研究；3）金属中心变价行为对固氮反应的影响及光催化固氮新途径的探索。在三年的项目执行期内，圆满的完成了上述研究任务相关成果发表在Nature Communications、Journal of the American Chemical Society、Science Bulletin等国际高水平杂志上。截止目前，在项目资助下已发表相关的学术论文16篇，其中第一/通讯作者论文14篇，申请授权发明专利2项；多次参加国内外学术会议并作邀请报告，与同行交流最新研究成果；项目培养硕、博士研究生多名。