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

Nickel oxide (NiO$_{\text {x}}\text {)}$based inverted perovskite solar cell is a structural type with immense potential for energy conversion efficiency. However, the reaction between NiOx 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 NiOx 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 NiOx, 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 NiOx-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%.