Light-actuated shape memory and self-healing phase change composites supported by MXene/waterborne polyurethane aerogel for superior solar-thermal energy storage

A flexible water-borne polyurethane (WPU)/MXene aerogel was applied as a supporting scaffold to confine polyethylene glycol (PEG) to fabricate photo-driven and flexible phase change material (PCM) composites. Firstly, the WPU@MXene aerogels with superior resilience were prepared via directional freeze-drying method. Secondly, the porous WPU@MXene aerogels were encapsulated with PEG by vacuum impregnation. The obtained WPU@MXene/PEG PCM composites possessed excellent dimension retention (98%@70 degrees C) along with high phase change enthalpy value (154.6 J g(-1)). Thanks to the three-dimensional interconnected structure and excellent photo absorption ability of MXene, the PCM composites showed superior solar-thermal energy conversion and storage capability. Additionally, combining the elasticity of the WPU@MXene aerogels and the solid liquid phase change of PEG ensured that the PCM composites realized excellent light-actuated shape memory and self-healing functions. This study enriches the way for developing flexible and multifunctional PCM composites, as well as shows enormous potential applications for the efficient utilization of solar energy.