针对汽车尾气日趋严峻的PM2.5污染，本项目提出了一种SiC/C多孔陶瓷多尺度设计的思路。通过将碳纤维、碳微球、SiC纳米线三个不同尺度材料组装成复合的微纳米网状结构多孔陶瓷，实现汽车尾气PM2.5的净化。通过微波水热碳化合成生物质碳连接碳纤维，使其构成一个具有一定强度的碳纤维骨架，利用碳热还原在碳骨架中合成SiC纳米线，使碳纤维、SiC纳米线成为一个有机的整体，利用SiC纳米线的VLS生长机制在碳纤维骨架中负载金属催化剂，赋予多孔陶瓷催化的特性。拟通过研究微波水热碳化工艺参数、碳热还原工艺参数对所制备SiC/C多孔陶瓷微观结构和性能的影响规律，阐述多孔陶瓷中碳纤维、碳微球、SiC纳米线、金属催化剂之间的协同效应，为SiC/C多孔复合陶瓷多尺度设计提供理论依据。最后对SiC/C多孔陶瓷的力学性能、压降行为、抗氧化行为和PM2.5吸附行为的研究，评价其在汽车尾气净化的应用前景。

We propose a multi-scale method for the design of SiC/C porous ceramics to handle the PM2.5 pollution in the exhaust gas of automobile. The SiC/C ceramics is made up of carbon fiber, carbon sphere, and SiC nanowires, which is assembled with a reticular structure. Carbon fibers are bonded by the carbon synthesized by the hydrothermal carbonization of biomass. SiC nanowires are prepared by carbothermal reduction between carbon and SiO vapor. Metal catalyst is supported on the carbon fiber skeleton during the growth of SiC nanowire by the VLS mechanism. We provide a method for the fabrication of SiC/C porous ceramics. Effects of the parameters of the hydrothermal carbonization and carbothermal reduction on the microstructure and properties of the SiC/C porous ceramics are studied. The synergy effect among carbon fibers, carbon spheres, SiC nanowires, and metal catalyst is studied to provide a theory for the multi-scale design of the ceramics. Finally, the mechanical properties, pressure-drop, anti-oxidation and PM2.5 adsorption behavior of the porous ceramics were studied to evaluate its application in the purifying of automobile exhaust gas.