Enhanced thermal energy storage of polyethylene glycol composite with high thermal conductive reaction-bonded BN aerogel

Organic solid-liquid phase change materials (PCMs) achieve thermal energy storage through solid-liquid phase change and are widely used for heat dissipation in electronic devices. However, organic solid-liquid PCMs have low thermal conductivity and leakage issues during phase transition. Therefore, BN aerogels were made through supramolecular self-assembly, freeze-drying, and heat treatment. By adjusting the proportion of raw materials and heating rate, thermal conductive BN aerogel with reaction-bonded fibers was obtained, which can stabilize the shape and enhance the thermal conductivity of polyethylene glycol (PEG) through the thermal conductive 3D framework. The BN/PEG PCMs showed excellent phase change enthalpy of 183.07 g·J-1 (retained 97% of PEG), superb shape stability, and high thermal conductivity of 0.89 W·m-1·K-1 at 2.8 vol.% BN content. The BN/PEG PCMs have enhanced thermal energy storage ability for heat dissipation, especially in the electronic field that requires electrical insulation.