3D porous copper foam-based shape-stabilized composite phase change materials for high photothermal conversion, thermal conductivity and storage

Solar energy absorption and storage have attracted extensive attention and a number of potential phase change materials have been reported. In the current work, new shape-stabilized phase change composite materials are designed, which can integrate high solar energy absorption, heat storage and thermal conductivity. The composite phase change materials are composed of copper foam (CF) as the supports, carbon material (graphene oxide and reduced graphene oxide (RGO)) as surface modifiers, paraffin and PEG10000 as organic phase change materials. CF modified by carbon materials provides a large number of active sites for the adsorption of phase change materials, which are stable and not easy to leak. The surface temperature of the composite phase change materials can rise to 70 °C within 200 s. Compared with the pure phase change material, the thermal conductivity of the CF/RGO/paraffin is increased by 300%. Its latent heat enthalpy is 111.53 J/g, the photothermal conversion efficiency is as high as 86.68%. Our approach not only provides a new way for facile manufacturing of high-performance composite phase change materials, but also integrates the processes of solar energy utilization, which exhibit good optical absorption performance, fast thermal response and excellent thermal storage capacity.