Form-stable phase change nanocapsules with photo and electric dual responses for multipurpose applications in energy storage and conversion

State-of-the-art multifunctional form-stable phase change materials (FSPCMs) with photo-thermal and electro-thermal dual responses have shown great application potential in sustainable energy utilization. The preparation of photo- and electric-responsive FSPCMs by mixing nano-functional materials such as carbon nanotubes or graphene with phase change materials (PCMs) systems has been extensively studied. Herein, photo and electric dual-responsive nanocapsules ([email protected]@PPy) were designed and constructed by employing industrial paraffin wax (IPW) as the core PCMs, crosslinked polystyrene (CLPS) as the supporting inlayer via miniemulsion polymerization, and polypyrrole (PPy) as the dual functional outlayer via further fast-oxidative chemical polymerization. The resultant [email protected]@PPy exhibits good shape stability, ideal phase change enthalpy (114.2 J/g), excellent thermal stability, and cyclability. Furthermore, the PPy functional outlayer endows [email protected]@PPy nanocapsules with excellent solar light absorption capacity and electrical conductivity, resulting in ideal photo-thermal conversion efficiency (88.4%) and electro-thermal conversion efficiency (80.1%). Consequently, the synthesized [email protected]@PPy has broad application prospects in photo-thermal and electro-thermal conversion/storage fields. This study will not only provide new ideas for the design and synthesis of nanostructured multifunctional FSPCMs but also open up routes towards the development of FSPCMs for energy harvesting, conversion, and storage fields.