Significantly Improved <scp>High‐Temperature</scp> Energy Storage Performance of <scp>BOPP</scp> Films by Coating Nanoscale Inorganic Layer

Biaxially oriented polypropylene (BOPP) is one of the most commonly used commercial capacitor films, but its upper operating temperature below 105 °C due to sharply increased electrical conduction loss at high temperature. In this study, growing an inorganic nanoscale coating layer onto BOPP film's surface proposed suppress temperature, as well increase Four kinds layers that have different energy band structure and dielectric property are grown both respectively. The effect on high‐temperature storage performance has been systematically investigated. favorable materials appropriate thickness enable films a significant improvement in performance. Specifically, when aluminum nitride (AlN) acts layer, AlN‐BOPP‐AlN sandwich‐structured possess discharged density 1.5 J cm −3 with efficiency 90% 125 °C, accompanying outstandingly cyclic property. Both operation significantly enhanced, indicating efficient facile method provides important reference improve polymer‐based films.