Photo-triggered Hierarchical Porous Carbon-Based Composite Phase-Change Materials with Superior Thermal Energy Conversion Capacity

The insensitivity of organic phase-change materials to light greatly limits the application of solar-thermal conversion. In the present work, a novel self-sacrificing template method was developed to prepare a hierarchical porous carbon (HPC) material with a large specific surface area using easily available starting materials of sucrose and sodium bicarbonate. The organic phase-change material of paraffin wax (PW) was consequently incorporated into the HPC to obtain shape-stabilized composite phase-change materials [composite phase-change materials (CPCMs)] with superior solar-thermal conversion ability. The prepared CPCM exhibits superior thermal performance, shape stability, cycle stability, and sunlight-absorbing ability. Also, the CPCM has a rather stable phase-change enthalpy of about 152 J/g even after 1000 heating–cooling cycles. The solar-thermal conversion efficiency of CPCMs is found to be as high as 89%. This work might provide a facile low-cost method for designing and synthesizing shape-stabilized phase-change materials based on porous carbon materials with potential applications in the solar-thermal energy storage and conversion.