Analysis and characterization of etched silica aerogels
Analysis and characterization of etched silica aerogels
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DOI：
10.1007/s10971-020-05256-5
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发表时间：
2020-02-20
影响因子：
2.5
通讯作者：
Carroll, Mary K.
中科院分区：
文献类型：
--
作者：
Stanec, Allison M.;Anderson, Ann M.;Carroll, Mary K.
二氧化硅气凝胶是独特的材料，其特性使其可用于多种应用。它们是纳米多孔的，密度低，表面积大，导热率低，并且相对半透明。最近，展示了使用 CO2 雕刻和切割系统将各种图案（包括文本和照片）蚀刻到二氧化硅气凝胶的表面上，同时对本体气凝胶的损坏最小；然而，气凝胶表面改变的机制尚不清楚，损坏的程度也未量化。在本文中，我们使用扫描电子显微镜 (SEM)、傅里叶变换红外光谱 (FTIR) 和气体吸附分析，展示了使用 CO2 激光雕刻和切割系统蚀刻和切割二氧化硅气凝胶材料的效果。蚀刻气凝胶材料的 SEM 分析显示出熔化的证据。与未蚀刻的材料相比，气凝胶整体的蚀刻部分的表面积较低，而孔径较大。 FTIR 显示二氧化硅气凝胶蚀刻过程中分子水平上几乎没有发生结构变化。
Silica aerogels are unique materials with characteristics that allow them to be used in a wide variety of applications. They are nanoporous, with low density, large surface area, low thermal conductivity, and they are relatively translucent. Recently, the use of a CO2 engraving and cutting system to etch a variety of patterns, including text and photographs, onto the surface of silica aerogel with minimal damage to the bulk aerogel was demonstrated; however, the mechanism by which the aerogel surface is altered was not understood and the extent of the damage not quantified. In this paper we present results on the effect of etching on, and cutting through, silica aerogel material with a CO2 laser engraving and cutting system, using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and gas adsorption analysis. SEM analyses of the etched aerogel material show evidence of melting. Surface areas of the etched portion of aerogel monoliths are lower compared that the unetched material while pore diameters are larger. FTIR shows that little structural change occurs on the molecular level during etching of the silica aerogel.