Development of hybrid graphene–biochar–metal foam composites phase change materials for building applications

Abstract Innovative research into thermal energy retention materials that improve interior thermal efficiency and lower overall energy consumption is prompted by the growing need for energy-efficient buildings. Phase change materials are known for their enormous latent heat storage capacity; however, issues with low thermal conductivity, leakage, and structural stability following repeated thermal cycling limit their practical application. This review work investigated the creation of hybrid biochar-metal foam PCM composites in order to overcome these problems. By adding graphene, rapid heat absorption and release rates are obtained, which considerably enhance thermal conductivity. Biochar, which is produced by pyrolyzing agricultural waste, offers a lightweight, extremely porous, economical, and environmentally acceptable matrix that reduces PCM leakage and promotes capillary-driven form stability. Benefits of metal foam include homogeneous heat distribution, good mechanical resistance, and structural strengthening. PCM is injected into hybrid scaffolds using the vacuum impregnation process to create form-stable composites that improve thermal transfer and minimize leakage. The findings demonstrate the use of composites in thermal-regulating wall panels, roofing systems, and passive energy-saving envelopes. For the future generation of high-performing, energy-efficient buildings, this PCM composite hybrid graphene-biochar-metal foam offers sustainable TES materials. Graphical abstract