Biomass-based phase change material gels demonstrating solar-thermal conversion and thermal energy storage for thermoelectric power generation and personal thermal management

The utilization of renewable biomass and the conversion of renewable energy are promising strategies for providing clean energy and meeting energy needs. In this work, a ternary phase change material gels (PCMGs) composed of octadecanol (OD), styrene-ethylene-butylene-styrene (SEBS) and hydroxylated carbon nanotubes (HCNTs) are proposed to realize the biomass utilization and solar energy harvesting. As a kind of biomass, OD possesses the characteristics of high phase change latent heat, low cost, renewability, environmental friendliness and biosafety. SEBS provides the crosslinked network to load the OD and introduce the free-standing feature. The HCNTs can realize the highly-efficient solar harvesting through the solar-thermal conversion. The Van der Waals force between SEBS and OD, the 7C -7C interaction between SEBS and HCNTs and the hydrogen bond between OD and HCNTs enable the excellent form-stability. Taking advantages of the synergistic effect of the functional components, the proposed biomass-based PCMGs demonstrate high thermal energy storage capacity of 183.04 Jg(-1), high solar absorbance of 95.68%, high cost-effectiveness of 3.92 x 10-5$J(-1) and high cell viability of 117.9%. The biomass-based PCMGs are effectively applied in the thermoelectric power generation and personal thermal management. This work creates a state-of-the-art alternative for the next-generation solar-thermal materials devices.