二氧化硅基纳米纤维气凝胶的研究进展

doi:10.19398/j.att.202204046

摘要/Abstract

摘要： 传统二氧化硅气凝胶是一种具有超轻、低导热系数、高孔隙率和高比表面积的三维结构多孔材料,但由于其力学性能较差,严重阻碍了实际应用。为解决此问题,将柔性二氧化硅纳米纤维引入气凝胶中作为骨架材料,在保留传统二氧化硅气凝胶优异性能的基础上,还可展现出良好的形状记忆功能和机械稳定性能。本文追溯了二氧化硅基纳米纤维气凝胶的发展历程,介绍了其制备方法及相关机理,梳理了当前为突破其力学性能差的限制所做的努力和改进,以更好地应用于空气过滤、油水分离、催化剂载体、吸附、隔热保温以及压力传感等领域,期望推动二氧化硅基纳米纤维气凝胶的进一步发展。

关键词: 二氧化硅, 纳米纤维, 气凝胶, 制备, 应用

Abstract: The traditional silica aerogels are three-dimensional porous materials with ultra-light, low thermal conductivity, high porosity and high specific surface area. Due to its poor mechanical properties, the practical application has been seriously restricted. To solve this problem, flexible silica nanofibers were introduced into aerogels as skeleton materials, which showed good shape memory function and mechanical stability on the basis of retaining the excellent performance of traditional silica aerogels. In this paper, the development of silica-based nanofiber aerogels was traced, the preparation method and related mechanism were introduced, and the current efforts and improvements made to break through the limitation of poor mechanical properties were summarized, so as to better apply silica-based nanofiber aerogelsto the fields of air filtration, oil-water separation, catalyst carrier, adsorption, heat insulation and pressure sensing. It is expected to promote the further development of silica-based nanofiber aerogels.

Key words: silica, nanofiber, aerogels, preparation, application

中图分类号:

TB33

卫智毅, 王慧, 余天培, 程辉, 马信, 李守柱. 二氧化硅基纳米纤维气凝胶的研究进展[J]. 现代纺织技术, 2022, 30(6): 231-241.

WEI Zhiyi, WANG Hui, YU Tianpei, CHENG Hui, MA Xin, LI Shouzhu. Research progress of silica-based nanofiber aerogels[J]. Advanced Textile Technology, 2022, 30(6): 231-241.

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