Solar cells fabricated by spray pyrolysis deposited Cu2CdSnS4 thin films

Cu2ZnSnS4 (CZTS) occurs in nature and is the most likely alternative to Cu(In,Ga)Se-2 (CIGS) thin film solar cells, which started to spread increasingly all over the world. CZTS is a very suitable absorber layer material for thin film solar cells due to containing cheap material. It has a 1.5 eV band gap that is appropriate for theoretical Shockley-Queisser limit values, and the large absorption coefficient (10(4) cm(-1)). Substitution of different metals and usage of low cost and easy controlled deposition systems may present advantages. Cu2CdSnS4 (CCTS) is a semiconductor with a band gap of 1.37 eV, and it has a large absorption coefficient over 10(4) cm(-1) that makes it a possible photovoltaic material. Its structure is similar to CZTS. In this study, Cu2CdSnS4 thin films were deposited by ultrasonic spray method at various substrate temperatures as an alternative absorber layer. The structural features of the thin films were determined by X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) surface morphology by Scanning Electron Microscopy (SEM) and optical band gaps by UV-VIS-NIR data. A CCTS-based solar cell with 1.14% power conversion efficiency was obtained using the most appropriate thin film according to optical and structural properties. (C) 2019 Elsevier Ltd. All rights reserved.