One-step hydrothermally assisted synthesis of CuZnSe thin film: photovoltaic application

Abstract

Herein, a one-step hydrothermal route was directly employed to synthesize copper-doped zinc selenide (CuZnSe) thin film. The synthesized CuZnSe thin film was analyzed for its optostructural, morphological, compositional and photovoltaic characteristics. The optical studies revealed that the deposited CuZnSe thin film exhibited a direct allowed type of optical transition with 2·32 eV bandgap energy. The structural studies demonstrated the formation of a pure cubic CuZnSe crystal phase structure with 57 nm crystallite size. The low- and high-resolution scanning electron microscopy images showed the formation of nanospherical surface morphology. The energy-dispersive spectroscopic analysis confirmed the presence of the elements copper (Cu), zinc (Zn) and selenium (Se) in the deposited thin film. Lastly, the photoelectrochemical properties were investigated using a two-electrode configuration in the dark and under light illumination from a 500 W tungsten filament lamp with an intensity of 30 mW/cm2 on an electrochemical workstation. In the dark condition, the current density–voltage (J–V) curve shows diode-like rectifying characteristics, and under illumination of light, it shows photovoltaic performance with 0·73% photoconversion efficiency. The photovoltaic results indicated that employment of one-step hydrothermally synthesized CuZnSe thin films has great potential for fabrication of photoelectrochemical solar cells.