Research on thermal energy storage of graphene-based phase change energy storage materials based on cross-dimensional collaborative modification of MXene and copper nanowires

As an intermittent energy source, the efficient utilization of solar energy relies on stable and efficient energy conversion and storage technologies. Phase change materials (PCM) have become ideal candidate materials for solar thermal storage due to their high energy storage density and reversible cycling characteristics. However, traditional organic solid-liquid phase transition materials are prone to leakage during the phase transition process and have a relatively low photothermal conversion efficiency, which limits their practical application. To address the above issues, this study designed a novel composite phase change material (CPCM). By collaboratively loading nanomaterials of different dimensions, such as copper nanowires (CuNWs) and MXene, into a graphene porous framework and encapsulating paraffin (PW), the reduced graphene oxide (rGO)/ CuNWs/MXene/PW (rGCuMPW) composite material was successfully constructed. Among them, the high light absorption capacity of MXene, combined with the excellent thermal conductivity of CuNWs, significantly improved the photothermal conversion efficiency (92.11 %) and thermal energy storage density (ΔH = 165.77 J·g −1 ) of the material. In addition, this material still maintains a stable phase transition enthalpy value after 100 cycles, demonstrating excellent cycle stability and reusability. The CuNWs-MXene synergistic modification strategy proposed in this study not only effectively reduces the leakage rate of organic PCM, but also significantly improves the performance of photothermal conversion and thermal energy storage, providing a new type of high-performance CPCM for the efficient utilization of solar energy.