Aerogel as a sustainable lightweight material: A comprehensive review of synthesis, properties, and applications

Aerogels are a kind of artificial, incredibly well-known light material with a highly porous structure and surface area. They are made from gels where the liquid component has been replaced with gas to maintain the integrity of the gel's framework. Even though many aerogel materials, whether organic, inorganic, or hybrid, are biocompatible, their promise has only been realistically used in non-medical fields of application in recent decades. Also, they have been used for a wide range of applications such as insulators, sensors, absorbers, catalysts, and filters due to their lightweight and porous structure. The synthesis, characteristics, and uses of aerogel have been the subject of several studies, which motivated the compilation and analysis of published information on these topics. This paper briefly reviews the synthesis process, properties (i.e., thermal, mechanical, optical, and acoustic), and potential applications of aerogel. Furthermore, the interactions between impurities and porous nanoparticles were also analysed. It has been found that the sol-gel method is widely used for the synthesis of aerogel, and silica is one of the most utilized materials for the production of aerogel, followed by rice husk, coconut coir, and graphene. The wonderful features of aerogel networking may be customized for certain applications with a deeper comprehension of material chemistry to manipulate material compositions (either organic or inorganic) and synthesizing conditions. In addition to a large number of contemporary investigations, the review also contains earlier studies that had a major impact on the advancement of aerogel-based materials throughout time, along with the challenges in processing and the future perspective of aerogel.