MXene/d-Mannitol aerogel phase change material composites for medium-temperature energy storage and solar-thermal conversion

Accelerate the development of medium-temperature phase change materials (PCMs) with high enthalpy of phase change and light absorption capability is very important for medium-temperature energy storage and solar thermal utilization. However, low energy conversion capacity and easy leakage limit the practical application of PCMs. To improve these properties of materials, a MXene/DM aerogel composite phase change material was prepared by self-assembly followed by freeze-drying of d-mannitol (DM) and MXene nanosheets using a simple solution blending method. The MXene/DM containing 20 wt% MXene has a high enthalpy (Hm) of phase change (202.7 J/g) with phase change temperature (Tm) of 153.3 °C, and still has good shape stability at 170 °C without leakage. In addition, MXene/DM has strong absorption ability in UV–Vis-NIR regions, with significant solar-thermal conversion efficiency of 88.1 %. The results indicate that the MXene/DM aerogel have comprehensive performance and have promising applications in medium-temperature thermal storage and photothermal conversion. [Display omitted] •A novel MXene-based aerogel is designed for medium temperature energy storage.•Melting temperature and phase change enthalpy of 20 % MXene/DM are 153.3 °C and 202.7 J/g.•The solar-thermal conversion efficiency of 20 % MXene/DM can reach 88.1 %