High performance composite phase change materials enhanced via evaporation-induced hydrogen bond network refactoring

Abstract

Composite phase change materials (CPCMs) with real-time thermal harvesting are in high demand in the solar-thermal energy conversion industry. However, poor heat conduction, lack of strength and leakage problem severely restrict its availability. In this study, we develop an evaporation-inspired, facile, and versatile strategy for manufacturing shape stable CPCMs from organohydrogels with enhanced thermal performances for advanced thermal energy storage and management. Organohyodrogels contained with graphene nanoplatelets (GNPs) served as the template. By oven-drying the organohydrogel, hydrogen bonding reconstruction would assist in the formation of a dense polymer layer to encapsulate PCMs, forming the non-leakage CPCMs. The strong capillary force generated during the oven-drying process would induce the alignment of GNPs, forming thermal conduction pathways. The as-prepared composite exhibits a high thermal conductivity (1.25 W m-1K−1), satisfactory latent heat storage (171.5 J g−1) and excellent Young’s modulus (8.3 MPa). When subjected to solar radiation, solar energy is converted to heat and stored inside the material, with a conversion efficiency as high as 95.8 %. The robust composite with high performance is expected to be an efficient and reliable thermal management material in solar-thermal energy conversion.