Nacre-like ceramics-based phase change composites for concurrent efficient solar-to-thermal conversion and rapid energy storage

Directly absorbing sunlight and on-site storing thermal energy via phase change processes are promising to achieve efficient and fast solar-to-thermal energy storage. However, the performance is severely inhibited by intrinsically low thermal conductivity and poor optical absorption capability of phase change materials (PCMs). We propose a strategy to achieve integrated efficient solar-to-thermal conversion and ultrafast energy storage by developing nacre-like ceramics embedded with titanium nitride (TiN) nanoparticles (NPs) contained PCMs. A high thermal conductivity of 25.63 W m −1  K −1 compatible with large phase change enthalpy of 157.93 kJ/kg are demonstrated. The excellent performance is attributed to ordered arrangement of silicon carbide ceramics and erythritol PCMs, just like microstructure of natural nacre . Meanwhile, the solar absorptance is improved by exciting localized plasmon resonances of TiN NPs in a broad band. Combination of high thermally conductive biomimetic skeletons with volumetric absorptive PCMs leads to a prominent enhancement of solar-to-thermal energy storage rate by 864%. This work paves a way for the application of ceramics in rapid and efficient solar energy harvesting and thermal energy storage .