Enhanced Thermal Conductivity and Phase Stability of Pickering Emulsion Phase Change Materials via Hexagonal Boron Nitride and Their Applications in Device Thermal Management Conversion

As electronic devices evolve toward higher integration and power density, localized heat accumulation poses greater challenges to device operational stability and safety. In this study, a water-in-oil (W/O) Pickering emulsion template method was employed to successfully prepare a hexagonal boron nitride h-BN-reinforced disodium hydrogen phosphate dodecahydrate/n-eicosane oil composite phase-change material (HPC-BN). This system employs Na2HPO4·12H2O as the aqueous phase and n-eicosane as the oil phase to form a water-in-oil Pickering emulsion, with h-BN introduced to establish thermal conduction pathways. The results indicate that the Pickering emulsion particles in the composite adhere tightly to the surface of the h-BN flakes, and the components exhibit good physical compatibility. This unique structure enables the composite to maintain a high latent heat of 193.8 J·g−1while increasing the thermal conductivity to 1.29 W·m−1·K−1, effectively slowing the temperature rise rate and limiting the maximum temperature of electronic devices in thermal management experiments. After 200 thermal cycles, the composite material still exhibits good thermal and structural stability, as well as satisfactory flame retardancy and corrosion resistance, providing insights for the application of composite phase-change energy storage materials in the field of passive thermal management for electronic devices.