Multifunctional shape-stabilized phase change composites based upon multi-walled carbon nanotubes and polypyrrole decorated melamine foam for light/electric-to-thermal energy conversion and storage

Flexible, high thermal conductivity, large heat enthalpy and multiresponsive of shape-stabilized phase change composites (SSPCCs) have received increasing attention in the relevant thermal energy management and storage applications. Herein, we developed a novel SSPCC with light/electric-to-thermal energy conversion and storage property, which was fabricated by encapsulating polyethylene glycol (PEG) into multi-walled carbon nanotubes (MWCNTs) and polypyrrole (PPy) decorated melamine foam (MF). The structural morphology, and shape-stabilization, thermal stability, thermal energy storage, thermal reliability, thermal conductivity, temperature regulation, photo/electro to thermal conversion properties of fabricated SSPCCs were explored. The results revealed that MF sponge framework decorated with MWCNTs by dip-coating and PPy by in-situ polymerization, showed highly porous structure and great absorption capacity (up to 97.9 wt%) for PEG. After impregnating PEG, the fabricated SSPCCs exhibited high latent thermal storage capacity of 165.1 J/g, excellent shape-stabilization and thermal reliability, improved thermal conductivity with 160.8 % higher than that of pure PEG, and great temperature regulation ability. Due to dual responses to light and electricity, the SSPCCs demonstrated a prominent photo/electro to thermal conversion capability. It provides an innovative route toward the design and development of multifunctional phase change composites for great potential in solar energy utilization, constructing energy conservation buildings, heat preservation, and infrared thermal stealth.