Improved photoabsorption and refined electrochemical properties of pseudocapacitive CuxO thin film electrode with Zn incorporation for applications in optoelectronic and charge storage

•Novel Pseudocapacitive Zn doped CuO Thin Film Electrode with enhanced supercapacitive performance was electrofabricated using simple two-electrode.•Microstructural studies revealed polycrystalline CuxO structure which contains the appearance of mixed phases of both Cu2O and CuO.•Comparative electrochemical properties of CuxO and Zn-doped CuxO films as supercapacitive electrodes were examined.•Highly stable pseudocapacitive response with improved specific capacitance of 263 Fg−1 and areal capacity of 5.83 mAh cm−2 at 1% vol. Zn dopant content was established.•The study demonstrates successful incorporation of Zn ion in CuxO lattice structure with improved supercapacitive and photocatalytic properties. [Display omitted] We report the consequence of Zn doping on some surface and electrochemical characteristics of CuxO nanostructured film, obtained via a facile and cost effective two electrode electrochemistry. Impact of Zn dopant on photoabsorption and supercapacitive responses of CuxO thin film electrode was examined. Microstructural studies revealed anisotropic growth of monoclinic and cubic CuxO crystals featuring alternate arrangements of O and Cu ions. Some structural properties of Zn-doped CuxO film were also found varying with Zn content. CuxO film exhibited red shift in its band structure and its optical energy band gap consequently declined from 2.62 to 2.20 eV with increasing Zn dopant. Zn-doped CuxO film also demonstrated highly stable pseudocapacitive response with improved specific capacitance of 263 F g−1 and areal capacity of 5.83 mA h cm−2. Lower series and charge transfer resistances as well as huge ohmic resistivity drop were also observed in the CuxO electrode with Zn dopant, indicating better ionic conductivity and charge storage capability. The study demonstrates successful incorporation of Zn ion in CuxO lattice structure and showed that supercapacitive and photocatalytic properties of CuxO thin electrode can be tailored by simply introducing Zn dopant impurity.