Current status, opportunities and challenges in catalytic and photocatalytic applications of aerogels: Environmental protection aspects

摘要

Aerogels are an exceptional class of materials which are of interest for several high-performance applications thanks to their extraordinary physical properties such as extremely high porosity, high specific surface area, and extremely low density combined with very versatile synthesis approaches. Since their invention by S. Kistler, various aerogels have been explored for catalytic and photocatalytic applications, though in the recent decades, several breakthroughs regarding different aspects ranging from more efficient catalysis in organic synthesis, energy-related processes, and catalytic environmental depollution by aerogels have been made. For both, catalytic and photocatalytic performances, aerogel monoliths prepared from sol-gel approaches accompanied with an appropriate drying technique, in particular supercritical point drying, have become striking alternative catalysts or catalyst supports compared to the presently used ones prepared from traditional wet synthesis approaches. In this article, aerogels in environmental remediation processes as heterogeneous catalyst and photocatalyst for depollution of air and aqueous media are fully addressed, and recent achievement in this context is thoroughly reviewed. (C) 2017 Elsevier B.V. All rights reserved.