Thermally superinsulating nanofibrous xanthan gum aerogels

Polysaccharide-based aerogels combine high porosity, low density, excellent biocompatibility, and tunable functionality, making them attractive for a wide range of applications. In this study, xanthan gum (XG) was used to fabricate nanoporous aerogels with finely structured nanofibers via metal-ion crosslinking, followed by solvent exchange and supercritical CO₂ drying. The resulting XG aerogels exhibit a high specific surface area (391 m²·g^-1), ultra-high porosity (98.7%), and low density (0.059 g·cm^-3), achieving an ultra-low thermal conductivity of 17.0 mW·m^-1·K^-1. The robust crosslinked network also provides excellent mechanical performance, with a compressive modulus of 2.75 MPa. Hydrophobic treatment enables it to adapt to a wider range of environmental conditions. These features make XG aerogels promising high-performance thermal insulation materials for applications in energy conservation and environmental protection.