气凝胶纳米材料

Nano Materials of Aerogels

作为一种纳米多孔材料,气凝胶具有纳米颗粒构成的连续三维纳米多孔网络结构,赋予其低密度、高孔隙率、高比表面积、大孔体积等特性。独特的结构特性使气凝胶在隔热、气体吸附分离、水处理、催化等方面具有良好性能,在航空航天、石油化工、新能源、科学研究、节能建筑、环保等领域有广泛的应用前景。在众多气凝胶中,传统的氧化硅和炭气凝胶被大量研究。最近,新型碳化硅气凝胶和表面改性氧化硅气凝胶获得广泛关注。碳化硅气凝胶隔热材料在有氧环境下的耐温性可达1200℃以上。疏水和氨基改性氧化硅气凝胶分别在水处理和气体吸附方面性能优异。综述了气凝胶的基本概念、结构特征和代表性研究工作,并重点介绍新型碳化物气凝胶和表面改性氧化硅气凝胶的最新研究进展。

As a nanoporous material with consecutive 3D network, aerogel has unique properties of low density, large surface area, high pore volume and porosity, leading to its excellent performances in thermal insulation, gas adsorption and separation, water treatment, catalysis, etc. Therefore, aerogels have promising applications in aerospace, industry, new energy, energy-efficiency building, environmental protection and many other aspects. Among all kinds of aerogels, traditional silica and carbon aerogels have been intensively studied. Recently, silicon carbide and surface modified silica aerogels are attracting wide attentions. Silicon carbide aerogel materials for thermal insulation are thermally stable in air at a high temperature over 1200℃. Hydrophobic and amine modified silica aerogels have outstanding performances in water treatment and gas adsorption, respectively. Hence, the definition, structural characteristics and representative studies of aerogels are reviewed, especially the recent advances of novel carbide aerogels and surface modified silica aerogels.