The present study aimed to investigate the electrochemical performance of nanostructured ZnO thin films (TFs) on the fluorine-doped tin oxide (FTO) substrate. The pure ZnO TFs, Al-doped ZnO TFs, and Cu-doped ZnO TFs were fabricated using electrospinning and post calcination at 400 °C. The electron microscopy studies revealed that electrospun nanofiber masks changed to dense TFs with an average thickness of 250–290 nm constructed by 10–20 nm connected nanoparticles (NPs). The doping of Al and Cu into ZnO TFs increased the hydrophilicity. Cyclic voltammetry (CV), electrochemical impedance (EIS), charge-discharge profiles, and Mott-Schottky (M − S) analysis were performed on the samples to evaluate the capacitance performance of pure and doped ZnO TFs. The semiconductor of TFs was n-type. The results confirm that all films can be used as a supercapacitor. Also, our results suggest that Cu-doped ZnO (CZO) TFs are the best choice for a supercapacitor electrode due to their 1.14 F cm−2 areal capacitance at 1 mA cm−2 applied current.
