Biomass based active-cum-passive aerogel heater with enhanced thermal insulation property derived from hollow cellulose kapok fiber for personal thermal management

Construction of biomass-based wearable aerogel heater with enhanced thermal insulation property plays a significant role in preventing heat loss for personal thermal management. Inspired by natural creatures’ utilization own hollow microstructures to resist the extremely cold surroundings, we report an eco-friendly strategy to construct calcium alginate (CA) /kapok fiber (KF)/carbon nanotubes (CNTs) active-cum-passive aerogel heater with desired economic feasibility, sustainability and efficient thermal insulation performance. The renewable cellulose hollow KF disrupts the heat transfer pathway and enabled CA/KF/CNT lower thermal conductivity (0.024 W/m·K) and ultralight density (0.027 g/cm 3 ). The CNTs in the aerogel heater not only provided excellent conductivity for realizing Joule-heating but also enhanced the photothermal conversion capability from solar irradiation, ensuring extra self-heating ability without power supply. According to energy-saving analysis, the total energy saved in China per year was 6.03 × 10 9 kWh when using the developed aerogel heater instead of the traditional heating method. This developed biomass aerogel heater in this work exhibits great potential to be applicable in the fields of wearable personal thermal management to enhance the adaptability of human body in cold environment. Our work may inspire the study of biomass-derived wearable heaters for solving global energy issues. Graphical abstract