© 2020, The Author(s).The present study aims to investigate the effect of (PVP: Sn-TeO2) interfacial layer on the electrical parameters of the Al/p-Si diode. For this aim, (Sn-TeO2) nanostructures were developed by the ultrasound-assisted method, and both their electrical and optical characteristics were investigated by XRD, SEM, EDS, and UV–Vis methods. The bandgap of Sn-TeO2 was found as 4.65 eV from the (αhυ)2 vs (hυ) plot. The main electrical parameters of the Al/p-Si diodes with/ without (PVP: Sn-TeO2) interlayer, such as ideality factor (n), zero-bias barrier height (Φ0), and series resistance (Rs), were calculated by applying and comparing two methods of thermionic emission theory and Cheung’s functions. These results show that the presence of the (PVP: Sn-TeO2 interlayer, along with the increase of Φ0, and the decrease of n and Rs, led to a significant increment in the rectification of MPS when compared to MS diode. The current-transport mechanisms (CTMs) of them were examined through the forward LnIF − LnVF and reverse LnIR − VR0.5 bias currents, and then, the Poole–Frenkel and Schottky field-lowering coefficients (β) were calculated and obtained its value from the theoretical and experimental methods showed that the mechanism of the reverse current of MS and MPS diodes is governing by the Schottky emission and Pool-Frenkel mechanism, respectively.