Anisotropic Rotunda‐Shaped Carboxymethylcellulose/Carbon Nanotube Aerogels Supported Phase Change Materials for Efficient Solar‐Thermal Energy Conversion
Nannan Zheng, Hao Pan, Zelong Chai, Zhimeng Liu, Fengyu Gao, Ge Wang, Xiubing Huang
Abstract
Abstract For the drawbacks of phase change materials such as poor shape stability and weak solar‐thermal conversion ability, a rotunda‐shaped carboxymethylcellulose/carbon nanotube aerogel (CA) with three‐dimensional network was constructed by freeze casting with a special mold, and then impregnated with polyethylene glycol (PEG) in this work. The PEG/CA had an enthalpy of 183.21 J/g, and a thermal conductivity of 0.324 W m −1 K −1 , which was 57 % higher than the pure PEG. The ability of PEG/CA to convert solar energy to thermal energy was a positive correlation between the inclusion of CNTs and the composite material‘s thermal conductivity. Under simulated sunlight, its solar‐thermal conversion efficiency reaches 94.41 %, and after 10 min of irradiation, the surface temperature can reach 65 °C and the internal temperature can reach 44.67 °C. This rotunda‐shaped PEG/CA is promising for the efficient use of renewable solar energy due to its strong solar‐thermal conversion and thermal storage capabilities.