No abstract

Transition metal chalcogenides(TMC) have been studied for their potential applications in optoelectronic devices such as light emitting diodes, solar cells, photodetectors, field effect transistors etc. Their unique structural, versatile electronic and optical properties, non-toxic chemical nature and abundance are some of the properties that have attracted tremendous attention of researchers. In this study, optimized junctions formed between zirconium sulphide(ZrS2) and Copper zinc tin sulphide(CZTS), Cupper indium sulphide(CIS), Cupper indium selenide(CISe) and Cadmium telluride(CdTe) absorber layers have been explored and compared using the Solar Cell Capacitor Simulator(SCAPS) for photovoltaic applications. The impact of operating temperature, illumination intensity, series and shunt resistances on cell performance has been discussed in details. Comparative study concluded that the Al-ZnO/ZrS2/CZTS structure presents the best efficiency of 9.72% at room temperature. Other performance parameters obtained are 25.16mA/cm2(Jsc), 0.61(Voc) and 68.86%(FF). External quantum efficiency(EQE) response has also been examined under AM1.5 spectrum for different device model. The simulation results suggest that n-ZrS2 can be used as an excellent buffer layer to fabricate environmental friendly and non-toxic solar cells.

Solar Cell Capacitance Simulator(SCAPS) program has been used to study JV characteristics and spectral response of ZrS2/CZTSSe heterostructure. The proposed cell performance has also been compared with ZrS2/CZTS and ZrS2/CZTSe junctions. In the present study, performance parameters have been calculated by varying Se concentration with an exponential grading law in SCAPS for ZrS2/CZTSSe heterostructure. CZTSSe bandgap can be easily tuned by varying the Se and S content. Optimized composition ratio of S/(S+Se) presented an efficiency of 16.50% and the simulated results have been interpreted for higher content ratio of 0.44. At this composition, short circuit current density, open circuit voltage and fill factor attained were 35.54 mA/cm2, 0.6342 V and 73.23 % respectively. The influence of layer thickness, bulk defect density, electron affinity and relative permittivity on solar cell performance parameters have also been studied.