Mesoscopic conductivity and trap distribution characteristics in the interfacial region of polypropylene/MgO nanocomposites with high energy storage density

•The combination of high-throughput simulations and experiments was used to study the interfacial trap properties of PNCs.•The mesoscopic conductivity and trap energy distributions of the interfacial regions in PNCs were obtained.•The shape of the trap distribution in the interfacial region does not change, but only the trap energy changes with the increase in nanofiller content.•The relationship between the aggregated structure in the interfacial region and the mesoscopic distribution characteristics of traps is revealed.