Eicosane-based thermo-conductive phase change composite for efficient capture solar energy and using in real-environment as power source

Abstract

With the increasing shortage of fossil energy, it is urgent to develop a phase change composite with exquisite thermal conductivity and excellent enthalpy for efficient capture solar energy and integrate with a thermoelectric generator (TEG) to achieve high power output density (>15 W m−2), so as to solve the global energy crisis. Therefore, it is necessary to put forward requirements for thermal conductive performance and latent heat in designing phase change materials (PCMs). In this study, a thermo-conductive phase change composite with thermal conductivity of 1.53 W m−1 K−1 and enthalpy of 203.5 J g−1 enabled by three-dimensional single crystal nanodiamond (3D-SCND) framework was constructed for the first time via ice-template assembly and vacuum impregnation strategy. Benefited from the elaborate structure, it can realize fast but uniform transfer of heat flux, which is great for accelerating the solar energy storage and further reducing the energy loss during the solar-thermal-electric conversion. Due to derive from high energy density and rapid heat energy output capability of our PCM composite, not only solar-thermal energy conversion efficiency reaches up 90.2%, but also generate an effective real-environment thermoelectric output power density of 22.7 W m−2 using with a TEG device. Our strategy is very effective for fabrication high-performance PCMs for efficient capture solar energy to solve the global fossil energy crisis.