Device design and optimization of all Perovskites based heterojunction solar cell

The SCAPS-1D simulation package is employed to examine the RbGeBr 3 /RbGeI 3 perovskite heterojunction, aiming to achieve a notable improvement in quantum efficiency when compared to a single layer of RbGeBr 3 perovskite. Moreover, the higher energy levels lead to a strengthening of the cell’s field, helping in the movement of carriers generated by sunlight, ultimately enhancing the device’s efficiency. Alongside this, we perform admittance and impedance spectroscopic calculations to thoroughly explore the impacts of deep defect states. As a result, the improved device exhibits a power conversion efficiency that surpasses 31%, marking a notable advancement from single absorber’s efficiency of 23.01%. The SCAPS-1D simulator is utilized for conducting capacitance-voltage, Mott-Schottky, and conductance-voltage analyses. This comprehensive investigation examines the differences in the band structure and recombination rates. This study proposes heterojunction structure aimed at the production of efficient inorganic and lead-free perovskite solar cells, presenting novel concept for future investigations in this field. • Niobate compounds are studied for solar applications under biaxial strain. • We analyzed dynamical stability, electronic structure, and optical characteristics using DFT and SCAPS simulations. • The compounds are non-magnetic indirect bandgap semiconduc- tors with LNO, KNO, and RNO bandgap energies of 1.964, 1.897, and 1.844 eV, respectively. • Increasing biaxial strain lowers the conduction band edge, reduc- ing the bandgap at +5% strain. • Increased strain leads to a red shift in the optical band gap, boost- ing photovoltaic potential. • High absorption coefficients and little energy loss are reported. • The most efficient and stable perovskite material is RNO.