Impact of Ag Doping on the Structural, Optical, and Photovoltaic Properties of MAPbI2Br Thin Films

Abstract Using the spray pyrolysis process, the work shows the production of pristine and 6% Ag-doped methylammonium lead iodide bromide (MAPbI2Br) film. Through X-ray diffraction analysis, it was found that Ag doping led to a significant increase in grain size to 29.64 nm, alongside reductions in dislocation line density to 5.39 x1014 m-2 and d-spacing to 3.18 Å, while maintaining the native cubic crystal structure of MAPbI2Br. This research demonstrates a reduction in deep-level trap states with Ag doping, along with a significant narrowing of the band gap to 1.91 eV in the 6% Ag-doped MAPbI2Br. Moreover, the refractive index and extinction coefficient increased to 2.54 and 2.13, respectively. Regarding solar cell performance, all cells demonstrated encouraging outcomes; still, the 6% Ag-doped cell distinguished itself with a fill factor of 0.82, an open-circuit voltage of 1.07 V, an outstanding short-circuit current density of 11.31 mA/cm², and an efficiency of 10.03%. These results highlight the effectiveness of Ag doping in improving perovskite solar cell technology, marking a notable progress in this field.