Structural, Morphological and Optical Characterization of Copper Antimony Sulphide CuSbS2 Thin Film Deposited by Spin Coating for Photovoltaic Applications

Solar energy is the most abundant renewable energy source on the earth surface. For many years, research has been done on making use of this source of energy. The current CdTe solar cell technology has good efficiency. However, large scale manufacture of CdTe PV modules are constrained due to the limited Te elemenet and the water soluble Cd element poses hazardous effects. The thickness of Cd has been reduced in the recent production from 3-8 nm to 0.5-1.28 nm but it remains poisonous and expensive. As an alternative, CIGS has been used but it is equally expensive. CuSbS2 is a very potential none poisonous and more abundant absorber materials for thin film solar cells yet its potential has not been fully reached. In this research, a homogenous solutions of CuSbS2 stochiometric ratio of 2.5:1 was deposited on a glass substrate by spin coating and then samples annealed at various temperatures ranging from 100 0C to 400 0C. X-ray diffraction showed that the control sample had amorphous structure as the crystallinity of annealed samples increased with increase in annealing temperatures. The d-spacing decreased with an increase in annealing temperature. Similarly, band gap energy decreased from 2.35 eV- 1.85 eV with an increase in annealing temperature. These results are in agreement with the earlier reports in literature.