Electro- and photo-thermal energy conversion investigation of polyethylene glycol infiltrated porous carbon aerogels

Due to the insulating nature of organic phase change materials, it is impossible to directly trigger latent heat thermal energy storage via an electrical way. In this work, through crosslinking, freeze-drying and pyrolysis, the interconnected carboxymethylcellulose sodium-derived carbon aerogel (abbreviated as CCA) with high porosity, good solar-thermal conversion capability, electrical conductivity, and mechanic strength is firstly fabricated successfully. The organic phase change material of polyethylene glycol (PEG) is then infiltrated into the CCA via vacuum infiltration to obtain the PEG/CCA15 composite phase change materials that melt at 52.1 °C with latent heat of 173.4 J/g. Electro-thermal test results display that PEG/CCA15 composite present low resistance (1.64 Ω), high electrical conductivity (4.201 S/cm) and excellent electro-thermal energy conversion efficiency (55.6 % under applying 1.4 V). Further results also show that PEG/CCA composites exhibit good photo-thermal energy storage and release abilities. Our results indicate that the as-prepared PEG/CCA15 is a potential candidate to be applied in electrical/solar energy utilization.