Fig. 3: Microstructure and capacitive properties of NBBSCT-NN@A/PEI-AlN/PEI-TE bilayer nanocomposites.

a The cross-section morphology, EDS elemental mapping images of b Na and c N of NBBSCT-NN@A/PEI-AlN/PEI-TE bilayer nanocomposites. d Temperature dependence of the εr and tanδ of pristine PEI, and NBBSCT-NN@A/PEI and NBBSCT-NN@A/PEI-AlN/PEI-TE nanocomposites. e Dielectric model of the bilayer nanocomposites (J and δ being conduction current density and electrical conductivity, respectively). f Weibull distributions and Eb, and g unipolar D-E loops and capacitive performances (the inset) of the bilayer nanocomposites during 25–150 °C. h Overall capacitive properties of the bilayer nanocomposites at 25 and 150 °C. i Energy storage performances of pristine PEI, and NBBSCT-NN@A/PEI and NBBSCT-NN@A/PEI-AlN/PEI-TE nanocomposites at various electric fields.