Preparation of wheat straw ash derived silica aerogel materials via ambient pressure drying

摘要

The wide range of applications of the silica aerogels are typically restricted by the high cost of the raw materials and cumbersome production processes, the high performance of the materials in terms of low density and high specific surface area was diluted by such blemishes. In this work, the silicon precursor has been extracted from a cheap and bio-derived wheat straw ash by using 'two-steps' acid-base method, the wetgels derived from wheat straw was silylated and dried under ambient pressure condition. The crystalline structure, morphology and the pore structures of the precursor and resulting gels were analyzed by the x-ray diffraction, scanning electron microscopy and N_2 adsorption, which leads to aerogel-like material with a density, specific surface area and porosity of 0.15 g/cm~3, 650 m~2/g and 95% respectively.