Theoretical Aspects of Ba₂AsNbO₆ Based Efficient Photovoltaic Device: Design and Optimization

In this study, we investigate the band alignment by examining an electron transport layer WS₂ and an absorber layer (Ba₂AsNbO₆), alongside four compatible copper based hole transport layers Cu₂O, CBTS, CuSCN, CuI. This analysis is presented schematically, proposing an appropriate architectural design for the newly introduced double perovskite oxide absorber material (Ba₂AsNbO₆) in a photovoltaic device configuration, specifically FTO/WS₂/Ba₂AsNbO₆/Cu₂O/Au. Our findings indicate that the newly proposed photovoltaic device demonstrates impressive photovoltaic parameters, including an open circuit voltage of 1.2603 V, a short circuit current density of 26.91 mA/cm², a fill factor of 85.82%, and a power conversion efficiency of 29.11%. Furthermore, the various parameters of the absorber layer, including thickness, acceptor doping density, acceptor defect density, and interfacial defects, have been optimized. Testing the device’s performance at various operating temperatures indicates that standard temperature is most suitable for optimal performance of the device. We also investigate the thickness-dependent complex impedance, frequency-resolved admittance spectroscopy, and capacitance measurements, observing a decrease in impedance with an increase in thickness, accompanied by a commensurate augmentation in conductance. The results provide valuable insights into the system’s electrical properties as functions of frequency, indicating potential pathways for improved device performance