Dual-Functional Polyimide-Based Phase Change Composite Aerogels with Latent Heat Storage and Radiative Cooling Capabilities for Energy-Efficient Buildings

• • CPIF/PI aerogels (CPs) were produced by electrospinning, freeze-drying, and thermal imidization, then vacuum-impregnated with molten PEG to form CPPCMs, and finally BN-coated to yield shape-stable BN@CPPCMs; this multistep route is compatible with roll-to-roll electrospinning and vacuum impregnation, enabling scalable production of building-integrated thermal management panels. • • CPIF enhances the thermal conductivity of BN@CPPCMs and, via compatibility with the PI matrix, improves sample stability; the PI backbone provides high-temperature resistance, preventing leakage and structural collapse during repeated phase transitions, which is critical for long-term building envelope applications. • • The BN coating increases solar reflectivity of BN@CPPCMs, significantly reducing their temperature during operation; this mitigates the thermal accumulation that degrades single radiative coolers, extending service life and maintaining cooling performance under continuous solar irradiance. • • The dual-functional composite integrates latent heat storage and radiative cooling, achieving high enthalpy efficiency and effective temperature regulation; by decoupling solar-thermal conversion/storage from passive radiative cooling, it addresses the 60% building energy consumption attributed to heating and cooling, offering a drop-in retrofit for energy-efficient building envelopes.