Biomass porous carbon/polyethylene glycol shape-stable phase change composites for multi-source driven thermal energy conversion and storage

Limitations of leakage and simplicity of functionality of phase change composite (PCC) gravely impede its wide application and propulsion especially in the fields of energy storage. In this paper, carbonized delignified basha wood (CDW) covered with polyvinyl alcohol (PVA) is applied as a matrix of PCC, a series of polyethylene glycol (PEG)-based shape-stable phase change composites (SSPCCs) with superior mechanical properties, and multiple energy conversion abilities were fabricated via simple chemical treatment and physical impregnation. The obtained SSPCCs with PVA demonstrate high phase change enthalpy (152.9 J/g for melting enthalpy and 147.2 J/g for crystallization enthalpy) and achieve 3.84 times increase in pressure resistance compared to the CDW simultaneously. Moreover, it exhibits an 86.3% PEG loading ratio and 97.7% relative enthalpy efficiency which empowers SSPCCs with outstanding thermal energy storage and thermal conversion capabilities including photo-to-thermal conversion and electro-to-thermal conversion. Besides, the addition of Fe 3 O 4 nanoparticles endows SSPCCs with excellent magnetic-to-thermal conversion performance, which broadens the path of energy transformation. These findings could guide the fabrication of high-performance and sustainable materials in the fields of energy storage and conversion.