Mechanosynthesis of semiconductor nanocrystalline Cu2ZnSnSe4 for solar cells

Abstract

Cu2ZnSnSe4 is a promising material that can be used to make low-cost, high-efficiency thin-film solar cells. The present study, we established a simple and efficient approach for producing a single-phase Cu2ZnSnSe4 bulk material from fundamental precursors (Cu, Zn, Sn and Se) using dry ball milling. After every two hours of the dry milling process, X-Ray Diffraction (XRD) and Raman Spectroscopy investigations were carried out to investigate the movement towards single phase Cu2ZnSnSe4 and the concurrent secondary phase depletion. The development of Cu2ZnSnSe4 materials that crystallize in a Kesterite system is shown by the prominent diffraction peaks. The crystalline size of the materials is 10–20 nm and dislocation density is 3.02–3.22 ×1015 lines/m2. UV–Vis spectroscopy was used to investigate the optical properties of the materials. Using transmittance and reflectance data, the linear and nonlinear optical constants of Cu2ZnSnSe4 films were calculated and the bandgap value is 1.6 eV. Hence from these results we can conclude that the above synthesized powder can be used for the development of thin films via thermal or electron beam evaporations on desired substrate and also we can use for various energy harvesting applications as a photoabsorber.