Cellulose and nanocellulose aerogels, their preparation methods, and potential applications: a review

In this study, the preparation methods, types, and developments of cellulose aerogels are comprehensively reviewed and evaluated. Aerogels can be prepared from synthetic or natural organic or inorganic materials. However, cellulose-based aerogels have gained tremendous attention in the past few years because of their biodegradability, abundance, and nontoxicity. In this study, the extraction of cellulose from various sources using different methods is discussed. Moreover, preparation of nanocellulose materials using different processes is reviewed. The different types of solvents used to dissolve cellulose and the various drying methods employed in the preparation of cellulosic aerogels are reviewed critically with a focus on green methods. The recent developments in hybrid aerogels for various applications are also discussed. In addition, the areas requiring further investigation are highlighted, such as the effect of the cellulose source on aerogel properties.