Development of graphitic domains in carbon foams for high efficient electro/photo-to-thermal energy conversion phase change composites

•Development of 3–10 layers of graphene domains in hierarchical carbon foam.•Presence of ordered nanoporosity with micro/meso/maroporosity in the microstructure.•PCMs composites with high electric-to-thermal efficiency (up to 85%).•PCMs composites with high light-to-thermal energy conversion efficiency (91%).•Stable thermophysical properties after 200 frequent melting/solidification cycles.