稳定高效的碳化硅复合材料的设计、制备与性能研究

Silicon carbide is a kind of wide band gap semiconductor (Egap = 2.4~3.2 eV, depending on the type of silicon carbide) possessing visible light activity. The strong covalent bonding character between silicon and carbon has endowed silicon carbide with lightweight, high hardness, high thermal conductivity and chemical durability, good thermal stability and electron affinity features, etc. Being a class of non-toxic and inexpensive semiconductor materials, silicon carbide with excellent physical and chemical properties has been widely studied for energy, environment and catalysis applications. However, relatively rapid recombination between the photoelectrons and holes exists within the lattice of silicon carbide, and the surface of silicon carbide could be easily oxidized to form silicon dioxide by photo-generated holes during the photocatalytic process, thus limiting its application potential in above-mentioned areas. Recent studies have shown that it is expected to prepare stable and high-efficiency silicon carbide nanocomposites through rational structural design. To this end, the project intends to rationally design the micro/nano structure of silicon carbide to explore the key preparation techniques of stable and efficient silicon carbide nanocomposites, and coupled with systematic investigation of the composition, morphology and interface structure of the composite materials. Besides, the exact impact of structure on the composite performance will be clarified, which could offer useful theoretical guidance and experimental basis for preparing high-performance silicon carbide nanocomposites, and also further expand the application prospect of silicon carbide in the field of energy and environmental protection.

碳化硅是一种具有可见光活性的宽带隙半导体（Egap= 2.4-3.2 eV，取决于碳化硅的类型），硅和碳元素之间强的共价键结构特性使其拥有质轻高硬度、高热导率、高化学稳定性、良好的热稳定性和电子亲和性等特点。作为一类无毒廉价，同时又具有良好的物理、化学性质的半导体材料，碳化硅被广泛研究应用于能源、环境和催化等领域。然而，由于碳化硅晶格内的光生电子和空穴复合较快，且在光催化过程中表面易于被光生空穴氧化形成二氧化硅，从而限制了其在上述领域的应用潜力。已有研究表明，通过合理的结构设计有望制备稳定高效的碳化硅纳米复合材料。本项目拟通过设计合理的碳化硅微/纳结构，系统研究复合材料组成、形态以及界面结构等，探索稳定高效的碳化硅纳米复合材料的关键制备技术，阐明结构对复合材料性能的影响，为制备高性能的碳化硅纳米复合材料提供理论指导和实验依据，进一步扩大碳化硅在能源及环境保护等领域的应用前景。

碳化硅是一种具有可见光活性的宽带隙半导体（Egap= 2.4-3.2 eV，取决于碳化硅的类型），硅和碳元素之间强的共价键结构特性使其拥有质轻高硬度、高热导率、高化学稳定性、良好的热稳定性和电子亲和性等特点。作为一类无毒廉价，同时又具有良好的物理、化学性质的半导体材料，碳化硅被广泛研究应用于能源、环境和催化等领域。然而，由于碳化硅晶格内的光生电子和空穴复合较快，且在光催化过程中表面易于被光生空穴氧化形成二氧化硅，从而限制了其在上述领域的应用潜力。已有研究表明，通过合理的结构设计有望制备稳定高效的碳化硅纳米复合材料。本项目拟通过设计合理的碳化硅微/纳结构，系统研究复合材料组成、形态以及界面结构等，探索稳定高效的碳化硅纳米复合材料的关键制备技术，阐明结构对复合材料性能的影响，为制备高性能的碳化硅纳米复合材料提供理论指导和实验依据，进一步扩大碳化硅在能源及环境保护等领域的应用前景。