Superhydrophilic and oleophobic porous aerogel based on biomass carbon for solar-dirven interfacial evaporation

Abstract

Although photothermal materials (PMs) are widely utilized in pure water and seawater, there is less research on the design and preparation of multifunctional photothermal materials with organic dye adsorption and oil displacement properties. In this study, biomass carbon aerogel (BC) was prepared through a simple Ca²⁺ cross-linking and freeze-drying process. To enhance the antifouling performance of BC, hydrophilic and oleophobic chemical modification was conducted to obtain BC-SP. The contact angle of n-hexadecane can reach to 141.8°, which enable the extensive application of BC-SP in oil-bearing wastewater treatment. Notably, BC-SP exhibited exceptional light absorption efficiency (approximately 95%), excellent heat insulation performance (thermal conductivity 0.0650 W m^− 1 K^− 1), and rapid water transport capability. Under the irradiation of 1 kW m^− 2, the solar energy conversion efficiency can reach to 86.8%. After tested eight cycles, the evaporation efficiency remained relatively stable and can adsorb most organic dyes in dye wastewater. Therefore, the study of BC-SP in this paper may has broad practical application prospects.