The effect of replacing iron atoms instead of zinc of the quaternary compound CZTS

Abstract

In this article, the quaternary compound Cu2MSnS4 was prepared in a simple and inexpensive approach, where M is the iron (Fe) and zinc (Zn) atoms by the spin coating method on a glass substrate at room temperature (RT), as a result of replacing Zn atoms by Fe. Quaternary Cu2ZnSnS4 (CZTS) and Cu2FeSrS4 (CFTS) structural and optical properties have been studied successfully. The material has been identified by X-ray diffraction, and it was discovered that CZTS has a polycrystalline Tetragonal (kesterite) structure, whereas CFTS has a Tetragonal (stannite) structure. A reduction in the full width half maximum (FWHM) of the preferred plane implies a high degree of crystallization. The structural properties of the film surface, such as grain size and roughness, were studied by Atomic force microscopy (AFM). The results explain an increase in nanoparticle size and surface roughness when Fe is substituted by Zn in the CZTS structure. The absorption coefficient values of all designed compounds in visible regions are greater than 104/cm, and the results show that the absorbance coefficient increases with Fe add. The CZTS films showed an energy gap of 1.88 eV, and this value became 1.69 eV with substituted Fe instead of Zn.