Abstract:
Perovskite solar cell (PSC) is a modern competitor within a photovoltaic research
community. The power conversion efficiency (PCE) of a PSC has extended from 3.8% to
above 22%, which interprets one of the fastest growths in a PV community. Perovskite as a
light-harvesting layer has captivating photonic and electrical properties like long diffusion
length, high absorption coefficient, low bandgap, less defect density and less excitons binding
energy. Considering these properties, perovskite have become an outstanding choice for thinfilm
solar cells. Bandgap tunability of PSC makes them interesting with other established
solar cell technologies.
Planar PSC with mixed cations and halide perovskite were prepared which reveals better
performance in contrast with single cation/halide perovskite. In addition, bandgap of a
perovskite material can be tuned by incorporating mixed cations/halides into single
cation/halide perovskite. Mixed cations (MA, FA, Cs) with mixed anions (Br, Cl, I) was used
with different concentrations of MACl (0, 0.025, 0.05, 0.07M/L). MACl helps in the crystal
nucleation process. MACl0.025 exhibits a highest PCE of 16.4%. Perovskite with this
concentration produced large grain size and reduce the pinholes. Overall PSC performance
varies between MACl0.025 and MACl0.05. Moreover, device without encapsulation under a
dark environment with controlled relative humidity could still maintain 71% of the original
PCE after six days.
