Growth of copper indium diselenide ternary thin films (CuInSe2) for solar cells: Optimization of electrodeposition potential and pH parameters

Herein, copper indium diselenide ternary (CuInSe2) thin film has been deposited on Indium Tin Oxide (ITO) coated glass substrate by electrochemical deposition technique with different potential and pH solutions. CuInSe2 thin films were deposited by one-step electrodeposition before post-depot selenization at 450 degrees C for 30 min. The effect of potential and pH on the structural and optical properties of CuInSe thin film have been studied using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and UV-Visible spectrometer. According to the X-ray diffraction (XRD) measurements, it was observed that all samples exhibit prominent reflections (112), (204/ 220), and (312/116) of tetragonal CuInSe2. The films electrodeposited at-0.8 V potential shows growth and peak values increasing in the (204/220) crystal direction within a pH range of 2.2, whereas the films electrodeposited at pH 2.6 tend to favor an increase in (112) peaks. We also noticed an improvement in surface morphology and adherent of CuInSe2 thin films electrodeposited at-0.8 V applied potential from the solution having pH 2.6. The band gaps of samples electrodeposited at-0.8V potentials from pH 2.6, 2.4, and 2.2 solutions were 1.15 eV, 1.25 eV, and 1.21 eV, respectively. As part of our investigation, we used a Solar Cell capacitance simulator (SCAPS) to perform our electrodeposited films. The most effective Power conversion efficiency (PCE) was obtained for thin films electrodeposited at-0.8 V within the solution having pH 2.4.

Automated summary

In this study, copper indium diselenide (CuInSe2) thin films were deposited on ITO coated glass substrates by electrochemical deposition with different potential and pH solutions. The effects of potential and pH on the structural and optical properties of CuInSe thin films were investigated. The film deposited at -0.8 V potential in the pH 2.4 solution showed the highest power conversion efficiency.