Electrochemical synthesis of CZTS film as photocathode in photoelectrocatalyic fuel cells

The electrodeposition of copper-zinc-tin (CZT) alloy precursors with suitable stoichiometry and consisting mainly of intermetallic compounds, followed by sulfurization, is a promising method to form good quality CZTS thin films. In this work, Cu-Zn-Sn precursors forming intermetallic compounds were electrodeposited from an acidic solution on FTO substrates at room temperature and sulfurized to form p-type CZTS absorber layers. We studied the crystal structure and compositional characteristics of films before and after sulfurization. Also, a CZTS film was modified with CdS for application to solar water splitting. A photoelectrochemical water splitting reaction was investigated using a three-electrode reaction system composed of a FTO/CZTS/CdS, Pt plate, and Ag/AgCl as the working, counter, and reference electrodes, respectively, in an electrolyte solution. The effects of the concentration and acidity level of the electrolyte on the photocurrent density were studied. The microstructural properties of the synthesized p–n type catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) images, UV–vis diffuse reflectance spectroscopy (UV–vis DRS) and atomic force microscopy (AFM).

Keywords:

CZTS , Water splitting , Electrodeposition , P-n junction