CdS基光催化材料的制备及可见光制氢活性研究

项目名称： CdS基光催化材料的制备及可见光制氢活性研究

项目编号： No.51502106

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 一般工业技术

项目作者： 张金锋

作者单位： 淮北师范大学

项目金额： 20万元

中文摘要： 随着人口增长和工业化发展，由于开采化石燃料造成的能源危机和环境污染是当今人类即将面临的两大世界性难题，开发新型无污染可再生的替代能源势在必行。幸运地，利用半导体材料光催化分解水产氢可以直接将太阳能转化为化学能（H2)。由于CdS具有良好的太阳光谱响应范围和适合的导带边位置，受到广泛的关注。但由于单独的CdS光生载流子快速复合且易被光腐蚀，CdS的光催化活性很低，通常利用贵金属沉积在CdS材料表面增强其活性。本项目利用第一性原理计算，通过比较六方相和立方相CdS的电子结构及光生载流子的有效质量，从本质上揭示其光催化水产氢活性的差异，为提高CdS催化活性提供理论依据。为了得到高效低成本的CdS基催化材料，采用一步微波水热法地制备石墨烯/CdS纳米棒复合材料，还设计了没有电子中间体的直接Z型CdS/WO3光催化剂，并揭示石墨烯/CdS及CdS/WO3复合催化材料促进光生载流子分离及抑制光腐蚀的机理。

中文关键词： 光催化；可见光；氢气

英文摘要： With industrialization and rapid population growth, the energy crisis and environment pollution caused by the depletion of fossil fuels have been regarded as two main challenges in the near future. Hence, the development of alternative clean renewable, cheap and sustainable source of energy supplies is an urgent assignment. Fortunately, photocatalytic hydrogen production using semiconductor materials is one of the ideal methods for direct solar energy conversion into chemical energy (H2). CdS photocatalysts have attracted much attention due to their excellent solar spectrum responses and suited conduction band positions for H2O reduction. However, CdS alone shows very low photocatalytic performance because of larger recombination of photogenerated carriers and photocorrosion, and its good activity is always achieved by loading noble metals on the surface of materials. In this project, the difference of photocatalytic hydrogen production activity of cubic and hexagonal CdS is explained by their electronic structure and effective mass of photogenerated carriers from first-principles calculation, which can be regarded as theoretical basis for improving the CdS catalytic activity. To obtain highly activity and low cost CdS-base photocatalysts, graphene/CdS nanorod composites is prepared by a one-step microwave-hydrothermal method, and the direct Z-scheme CdS/WO3 photocatalyst without an electron mediator is designed by imitating the natural photosynthesis of green plants. In addition, the physical mechanisms of acceleration separation of photogenerated carriers and inhibition photocorrosion for graphene/CdS and CdS/WO3 photocatalysts are revealed, respectively.

英文关键词： photocatalysis;visible light;hydrogen