Role of facile synthesized V2O5 as hole transport layer for CdS/CdTe heterojunction solar cell: Validation of simulation using experimental data

This article presents the role of Vanadium Pentoxide (V2O5) as electron blocking-hole transport layer (EB-HTL) in Cadmium Sulfide (CdS) and Cadmium Telluride (CdTe) based heterojunction solar cells using simulation employing experimental data. Noble solvents Thiolamine and methanol with diethaylamine were used to synthesis of CdS and V2O5 respectively using sol-gel method. At first, the optical and electrical properties of CdS, V2O5 spin coated thin films deposited on glass substrate were investigated experimentally. Then, these experimental data of optical and electrical properties were used to simulate FTO/CdS/CdTe/Al and FTO/CdS/CdTe/V2O5/Al heterojunction solar cells. The simulation was carried out using SCAPS-1D simulator, where data of CdTe absorber layer were taken from reported work. Simulations were performed at a range of concentration, thickness, defect density and temperature to conjecture the better cell efficiency and efficacy of V2O5 as EB-HTL. At carrier concentration of 1 x 10(17) cm(-3), 1 x 10(16) cm(-3) and 1 x 10(18) cm(-3) for CdS, CdTe and V2O5 respectively, the optimum thickness was found to be 0.100 mu m, 1.00 mu m and 0.100 mu m for the corresponding material layers respectively with interface defect density (donor and acceptor) of 2.5 x 10(17) cm(3) at a junction temperature of 300 degrees C (573 K). Simulation results reveal that, the designed FTO/CdS/CdTe/V2O5/Al heterojunction solar cell shows the highest efficiency of 23.50% with enhanced open circuit voltage of 0.708 V, current density of 44.41 mA/cm(2), fill factor of 75% compared to those of FTO/ CdS/CdTe/Al heterostructure (without EB-HTL) counterparts. Therefore, it can be envisage that, solution processed V2O5 as EB-HTL is a potential and flair material for CdS/CdTe heterojunction solar cells.