Polymer Nanocomposite Capacitors with Largely Reduced Conduction Loss Utilizing Wide-Bandgap Inorganic Nanofillers

Dielectric polymer film capacitor with high energy density and efficiency is one of the enabling technologies for the development of flexible electronics and power systems. Herein, we introduce wide-bandgap inorganic fillers into the polymer matrices to yield polymer nanocomposites. It is found that the leakage current is largely decreased, and the charge-discharge efficiency is significantly improved of the nanocomposites, especially at high fields and elevated temperatures, compared to polymer matrices. The increase in activation energy indicates that the presence of wide-bandgap nanofillers in the polymer matrix gives rise to a higher barrier to be overcome for occurring conduction processes. In addition, a strong dependence of high-field conduction behavior on the filler morphology is revealed. Compared to zero- and one-dimensional fillers, two-dimensional nanoplate enables the shortest hopping distance, and is the most efficient in inhibiting conduction loss of the polymer composites.