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Strong rigidity, low thermal conductivity, and short of multi-driven capabilities of form-stable phase change materials (FSPCMs) have limited their practical utilization. Herein, we report a shape-adaptable FSPCM with the coinstantaneous light/electro-driven shape memory properties and light/electro-to-thermal energy storage performance. The FSPCM is fabricated by incorporating the poly­(ethylene glycol) (PEG) into the cellulose nanofiber/graphene nanoplatelet (GNP) hybrid-coated melamine foam (CG@MF). The CG@MF/PEG FSPCMs show a good encapsulation effect, enhanced thermal conductivity, and large melting enthalpy (178.9 J g–1). Due to the high elasticity of MF and the excellent photothermal conversion and electrical conductivity of the GNP network, the CG@MF/PEG FSPCMs exhibit a remarkable light/electro-driven shape memory effect by activating the phase change process of PEG. Meanwhile, the CG@MF/PEG FSPCMs can effectively convert light or electric energy into heat energy and reposit the converted energy during the phase change process. Furthermore, the CG@MF/PEG FSPCMs possess excellent multiresponsive self-adhesion properties. A light-sensitive, shape-adaptable, and thermal-insulating container is further explored. This study provides routes toward the development of multiresponsive shape-adaptable FSPCMs for energy storage applications.

Organic phase change materials (PCMs) have attracted increasing attention in the solar energy utilization field for their large thermal energy storage density, appropriate phase transition temperature, and excellent chemical stability. However, the liquid leakage defect and poor solar-thermal conversion performance restrict their large-scale application. Herein, novel PCM composites with superior solar-thermal conversion efficiency, excellent form-stability, and improved thermal conductivity were successfully synthesized by introducing a dopamine-decorated MXene (Ti3C2T x @PDA) into a poly­(ethylene glycol) (PEG)-based polyurethane PCM. Ti3C2T x @PDA, which was covalently bound to polyurethane, acted as a photon capturer and molecular heater and converted solar energy to thermal energy, whereas the PEG-based polyurethane PCM could absorb and store the generated thermal energy through solid–solid phase transition. Sunlight irradiation experiments demonstrated that the solar-thermal conversion and storage efficiency of PCM composites (up to 90.1%) were significantly improved with the introduction of the MXene Ti3C2T x @PDA. Based on differential scanning calorimetry (DSC) analysis, PCM composites exhibited satisfactory phase change enthalpy in the range of 121.9–128.2 J/g. Moreover, the developed PCM composites possessed excellent form-stability, remarkable thermal reversibility, good thermal stability, and improved thermal conductivity. In conclusion, the synthesized PCM composites exhibited tremendous application potential in solar energy utilization field.