Erythritol phase change composites with a carbon foam-aerogel hierarchical scaffold for enhanced thermal protection

This study elucidates an attempt to develop a stable and efficient composite phase change material for mid-temperature solar thermal storage by incorporating erythritol (Ery) into a designed 3D porous carbon foam/carbon aerogel (CF/CA) scaffold. This work aims to tackle the challenge of significant supercooling, volume expansion, and liquid leakage associated with pure Ery. The Ery@ CF/CA Composite was synthesized via vacuum melting impregnation, using Ery loadings up to 79 wt% supported by the CF/CA scaffold. The optimal composite showed a dense structure with a melting point of 118.9 °C and a high latent heat of 272.4 J/g (for 79 wt.% Ery). Meanwhile, its thermal conductivity remained low at 0.939 W/(m·K) at 25 °C. After 5 cycles, the material showed no leakage or distortion, retained >90% of its enthalpy, and achieved a 26.98% reduction in supercooling. The improved thermal storage capacity and structural stability are attributed to the combined effect of the insulating carbon network and the high latent heat Ery. The findings provide the role of 3D carbon scaffold in stabilizing phase change materials and offer a promising materials strategy that can meet the future demand for efficient and reliable mid-temperature solar thermal storage systems.