Polysaccharide-based aerogels for thermal insulation, filters and battery application

Abstract

Polysaccharide-based materials with high potential to become a novel, sustainable thermal insulation and battery electrode material. The fact that polysaccharides are commonly found in biomass, gives great potential to develop sustainable processes and materials with exceptional physical properties. The aim of the presented research is exploitation of different polysaccharides and their feedstocks to develop sustainable aerogels for several applications as an alternative to current fossil-based plastic materials, traditional insulation, filters and as precursors for carbon-based electrode materials. IUPAC announced aerogels among the top 10 emerging technologies of 2023, thus making them lucrative for potential exploitation in various technologies. The project "GelSus" focuses on the production of cellulose aerogels with antimicrobial properties for sustainable food-packaging, filters and thermal insulation, whereas project "PISA" focuses on the pilot scale production of cellulose aerogels to be used as a sustainable thermal insulation in buildings. Additionally, lignocellulosic biomass, the most abundant organic material on Earth, has enormous potential as a feedstock for the production of carbonaceous materials for energy applications. The project "Charge" aims to use the invasive crab's shells as a feedstock for chitosan and carbon aerogels tailored towards battery applications in the sodium ion battery sector while project "Kolibri" aims at sustainable manufacturing of anode materials for lithium ion batteries from crab shell waste and recovered carbon black from old tires. In the project "AltholzAerogel" cellulose and lignin from fresh and waste wood are used for the production of polysaccharide and carbon aerogels. While the polysaccharide aerogels shall be used for the improvement of wood insulation boards the carbon aerogels are going to be tested in gas respiratory filters. Synthesis of polysaccharide aerogels requires extraction of the particular biopolymer from considered bio-waste feedstocks. The mentioned projects investigated optimal conditions for the extraction and synthesis processes. Additionally, material models for cellulose and chitosan aerogels were developed from molecular to product scale. The obtained results indicate significant potential of polysaccharide aerogels as novel, sustainable materials for several applications. The cellulose aerogels create an alternative to traditional insulative materials, while chitosan aerogels were studied in terms of potential precursors for carbon-based battery electrodes. The experimental and simulation results were compared and analyzed towards better understanding and synthesis optimization.