Effect of the precursors and synthesis methods on the optical and photoelectrochemical characteristics of SnS absorber layer

Abstract

Influence of the preparation method and different precursors are important for the absorber photovoltaic layer parameters of SnS. Synthesis of SnS compounds was carried out via two preparation methods; solid state reaction and hydrothermal; using different sulfur precursors. The morphology of particles and phase identification were studied using Field Emission Scanning Electron Microscope (FESEM) and X-ray diffraction (XRD) techniques. The XRD diffraction pattern of SnS revealed the existence of two crystal structure phases: the major is orthorhombic and the minor phase is tetragonal. The optical properties were determined using UV-Vis spectrophotometer showing absorbance peaks around 485 nm. The lowest bandgap of 1.74 eV is for SnS sample prepared from L-cystine. Electrochemical impedance spectroscopy (EIS) revealed that SnS cell prepared from L-cystine gave the lowest resistance of 171W. The photoelectrochemical measurements of this cell showed the highest power conversion efficiency per unit area of 2.5%.