Construction of room-temperature self-healing polyurethane-based phase change composites for thermal control and energy supply

Solar energy is the main cause of overheating in the cabin of cars on summer days, resulting in a large amount of fossil energy being used for temperature control in cars. However, the conversion of solar energy in a low-energy way to realize in-vehicle temperature controlling and reduce the consumption of fossil fuels remains a significant challenge. Herein, we report a room-temperature self-healing polyurethane (PU2) with excellent mechanical strength (10.4 MPa) to fabricate an energy conversion and supply composite (ST1/PU2) via combining with phase change microcapsules (MEPCMs), which efficiently realize invehicle temperature controlling. MEPCMs display superior phase transition enthalpy of 160.0 J/g, thermal conductivity 0.34 W/(m K) and encapsulation performance (71.9%) in ST1/PU2. The resultant ST1/PU2 exhibits outstanding cooling effect/thermal insulation upon a light intensity of 5.1 W/cm2, where the actual temperature was reduced by 28.5 degrees C compared to PU2. Furthermore, the self-healing triboelectric nanogenerator (S-TENG) based on ST1/PU2 provides continuous electrical signals and the healed S-TENG could be 100% recovered at 50 degrees C in 24 h, which shows great potential to significantly prolong the service life of devices. Consequently, this work will provide a new strategy to reduce the fossil energy consumption and promote the sustainability of flexible electronics.