Insights into sustainable aerogels from lignocellulosic materials

Abstract

Aerogels, the three-dimensional materials, have been considered to be revolutionary solid-state materials due to their highly porous structure, low density, large surface area, and low thermal conductivity, which can be applied in the many modern fields of industry. Since its discovery in 1931, research related to aerogels has expanded from the exploration of starting materials to synthesis routes and applications (e.g., thermal, sound insulation materials, and wastewater treatment). The limitations of conventional aerogels (silica, resorcinol/formaldehyde), which are unsustainable, non-biodegradable, and expensive materials has motivated researchers to seek alternative materials. In this regard, lignocellulose is a better candidate and thus has attracted the attention of the community. This review critically analyzes the current state-of-the-art in aerogel synthesis from lignocellulosic components and the entire lignocellulose biomass, focusing on the effects of synthesis routes and conditions on aerogel properties. Perspectives on pre-treatment, synthesis approaches, potential applications, and future development will be discussed.