© 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.In this research, for determining the effects of the (Gr-PVP) interfacial layer, two types of diodes (Au/n-Si and Au/(Gr-PVP)/n-Si) were performed on the same n-Si wafer with the same ohmic and rectifier contacts. Graphene-doped PVP nanocomposite film was grown on the n-Si wafer by a spin-coating method. Therefore, the basic electrical parameters of them were extracted from the I–V and Z-V-f characteristics and compared in detail. The higher values of n and lower values of BH obtained from Cheung’s functions compared to TE theory were ascribed to their voltage-dependent. The frequency-dependent diffusion potential (VD), doping-donor atoms (ND), depletion layer width (WD), surface potential (Ψs), Rs, and BH values of the MPS diode were also extracted from the impedance characteristics in the frequency range of 10–103 kHz.