Super tough and stable solid–solid phase change material based on π-π stacking

Abstract The solid–solid phase change materials (SSPCMs) have become the preferred materials in thermal energy storage via absorbing latent heat from ambient environment. However, the trade-off between the mechanical properties, stability and recyclability is still the obstacle and barrier for development of SSPCMs. Herein, we proposed a facile and novel strategy to prepare SSPCMs for address above issues by introducing π-π stacking to form physical crosslinking points in linear polyethylene glycol (PEG). The strong intermolecular forces formed by π-π stacking not only prevented leakage of the PEG even at 130 °C but imparted high temperature stability and excellent toughness (172.44 MJ/m3) to fabricated SSPCMs. It is worth mentioning that the prepared PCMs can be added with CNT in a simple process way to improve the photo-thermal conversion ability and thermal conductivity of SSPCMs. Besides, the as-prepared SSPCMs exhibited excellent flexibility, and were expected to be excellent thermal/photo energy storage materials for human thermal management and wearable devices.