Synthesis, characterization and hygrothermal behaviour of mesoporous silica high-performance desiccants for relative humidity buffering in closed environments
Synthesis, characterization and hygrothermal behaviour of mesoporous silica high-performance desiccants for relative humidity buffering in closed environments
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DOI：
10.1016/j.actamat.2011.09.016
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发表时间：
2012-01-01
期刊：
影响因子：
9.4
通讯作者：
Yang, H.
中科院分区：
文献类型：
--
作者：
Hall, M. R.;Tsang, S. C. E.;Yang, H.
合成了四种不同的介孔二氧化硅(MS)样品，以评价其作为候选快速响应干燥剂材料的性能。将它们的性能与传统干燥剂进行了比较。其目的是通过将湿热功能行为与微观结构组成相关联来实现湿热功能行为的调节。用小角X射线衍射仪、Brunauer-Emmett-Teller分析、Barrett-Joyner-Halenda分析和高分辨电子显微镜对孔结构进行了表征和验证。中孔网络的体积和平均直径是直接相关的，当增加时，大孔体积和整体孔隙率成比例下降，这表明中孔体积越大，孔壁厚度越小。用改进的瞬变平面源和差示扫描量热法对其热物性进行了表征。用改进的动态蒸气吸附(DVS)技术表征了蒸气储存和吸附/解吸响应速率。DVS响应时间t(EME)与中孔直径和中孔体积均呈正对数关系，而水蒸气渗透率则呈负相关。与硅胶、沸石、分子筛和膨润土等传统干燥剂相比，所有MS样品都具有更高的蒸汽存储容量和更快的DVS响应速度。(C)2011 Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
Four different mesoporous silica (MS) samples were synthesized for assessment as candidate rapid-response desiccant materials. Their behaviour was compared with that of conventional desiccants. The aim was to enable tuning of hygrothermal functional behaviour by correlating this with microstructural composition. Pore geometry was characterized and validated using small-angle X-ray diffraction, Brunauer-Emmett-Teller analysis, Barrett-Joyner-Halenda analysis and high-resolution transmission electron microscopy. The volume and mean diameter of the mesopore network are directly related, and when increased cause a proportional decrease in macropore volume and bulk porosity, suggesting that the pore wall thickness decreases at larger mesopore volumes. Thermophysical properties were characterized using modified transient plane source and differential scanning calorimetry. Vapour storage and sorption/desorption response rates were characterized using modified dynamic vapour sorption (DVS) techniques. The DVS response time, t(eme), has a positive logarithmic relationship with both mesopore diameter and mesopore volume, whilst vapour permeance appears to be inversely related. All MS samples had a significantly higher vapour storage capacity and quicker DVS response rate than the conventional desiccants, including silica gel, zeolite, molecular sieve and bentonite. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.