Improved performance efficiency of manganese dioxide nanoparticles passivated perovskite solar cells

Defect passivation is increasingly becoming a viable method of performance optimization in organic–inorganic methylammonium lead iodide perovskite-based solar cells. In this research, synthesized manganese dioxide (MnO₂) material via chemical method was used to sensitize all-solid-state halide perovskite solar cells (PSCs). Additionally, titanium dioxide (TiO₂) and reduced graphene oxide synthesized through Sol gel and Hummers’ methods, respectively were incorporated as electron transporting layer, and MnO₂ was used to enhance graphite counter electrode. ITO/rGO/TiO₂/CH₃NH₃PbI₃/Gr and ITO/rGO/TiO₂/CH₃NH₃PbI₃/Gr-MnO₂ planar PSCs were fabricated via spin coating technique, and exposed to solar illuminator in order to evaluate their photovoltaic performance. ITO/rGO/TiO₂/CH₃NH₃PbI₃/Gr-MnO₂ film showed a power conversion efficiency of 11.34% compared to 8.22%, for ITO/rGO/TiO₂/CH₃NH₃PbI₃/Gr film. The percentage enhancement value of 27.50% was realized with MnO₂ passivation. This research demonstrates that wide bandgap two-dimensional materials can tune the functionality of PSCs and afford a lead on designing of advanced passivation media to further tailor halide perovskite properties via grain boundary functionalization.