Biomass-Derived SiC aerogel scaffolds for multifunctional phase change Composites: Simultaneous Solar-Thermal energy harvesting and EMI shielding

Developing multifunctional form-stable phase change materials (PCMs) with high energy density and robust environmental adaptability is pivotal for sustainable thermal management. Herein, a facile and scalable “biomass-to-ceramic” strategy is reported to engineer potato-derived silicon carbide (SiC) aerogels as robust scaffolds for n -octadecane-based composites (SiCPCMs). Through sequential hydrothermal gelatinization and in-situ carbothermal reduction, the natural cellular architecture of potato was transformed into a 3D interconnected SiC framework. This rigid ceramic network not only effectively prevents liquid leakage via strong capillary forces but also serves as a highly conductive and dielectric skeleton. Consequently, the optimal SiCPCMs exhibit a high latent heat storage capacity (up to 234.3 J/g) with an impressive encapsulation efficiency of 87.22%. Furthermore, the integration of the SiC aerogel significantly enhances thermal conductivity by 96.40% and achieves a superior solar thermal storage efficiency of 91.51%. The composites also demonstrate excellent electromagnetic interference (EMI) shielding effectiveness of 33.03 dB in the X-band. Building energy simulations further reveal that deploying these SiCPCMs can reduce cooling energy consumption by approximately 42% in representative cities. This work establishes a sustainable paradigm for upcycling agricultural biomass into high-value multifunctional ceramics for next-generation green buildings and electronic protection.