Solvothermal synthesis of functionalized MOF particles to enhance energy storage stability of BaTiO3/UiO-66-NH2/PVDF/PI nanocomposite films

As dielectric film as the core device of capacitors, how to enhance its dielectric and energy storage performance is crucial for the application of film capacitors. To this end, we propose a solvothermal synthesis of metal-organic framework (MOF) material UiO-66-NH 2 to explore the potential application of MOF materials in the field of dielectric energy storage. BaTiO 3 nanoparticles and MOF fillers were selected to be introduced into the PVDF/PI matrix, and nanocomposite films were prepared by the spin-coating process, which showed a strong bonding at the micro-interface of the film and a uniform macroscopic thickness without obvious aggregation. The high porosity of UiO-66-NH 2 and the high dielectric constant of BaTiO 3 , as well as the high breakdown strength E b of the polymer matrix are utilised to synergistically promote the energy density and maintain good charge/discharge stability. Notably, the BU-X/PVDF/PI nanocomposite films demonstrated good energy storage performance and stable charge/discharge efficiency η. The results show that the BU-0.5/PVDF/PI nanocomposite film has an E b of 2190 kV/cm, an energy storage density of 3.73 J/cm 3 , and stable η ranging from 60 % to 94 %, which are superior to the pure BaTiO 3 /PVDF/PI nanocomposite film in terms of overall performance. In addition, the dielectric loss of the BU-0.5/PVDF/PI nanocomposite film is as low as 0.022. These findings indicate the good prospects for the development of MOF materials in the field of energy storage.