Study on Improving Efficiency of Perovskite Solar Cells through Controlling Humidity Conditions and Nickel Oxide Composition

Nickel oxide (NiO
_x
) based inverted perovskite solar cell is a structural type with immense potential for energy conversion efficiency. However, the reaction between NiO
_x
and the perovskite is a significant source of interface defects and energy losses. By manipulating the environmental humidity during fabrication, we effectively adjusted the composition of NiO
_x
and suppressed the interface reaction, resulting in reduced open-circuit voltage loss. Furthermore, a specific humidity environment help self-assembled monolayer (SAM) to formate more efficient dipoles on the surface of NiO
_x
, owing to the increased presence of hydroxyl groups at that particular humidity level. By appropriately elevating the humidity during fabrication, the built-in potential of SAM-modified NiO
_x
-based devices exhibited a remarkable increase. Attributable to the passivation effect and heightened dipole formation, the power conversion efficiency of the devices enhanced significantly, ascending from 17.44% to 20.23%.