Modification of hydrophobic PTAA layer with Al2O3 nanoparticle over large-area inverted perovskite solar cell

Poly (triaryl amine) [PTAA] has been used as a promising hole-transport layer (HTL) for the p-i-n device architecture to fabricate high-efficiency perovskite solar cells (PSCs). Further improvement of perovskite device stability and efficiency is essential to make them commercially viable. In the present work, incorporating Al2O3-nanoparticles (NPs) at the PTAA/Perovskite interface exhibits enhanced surface coverage and reduced surface roughness, facilitating improved charge extraction and reduced charge recombination. The PTAA layer passivated with 2.0 wt% Al2O3-Nanoparticles (NPs) boosted the PCE of the PSCs from 11.11 % to 14.72 % (0.25 cm2 cell) and from 7.2 % to 9.2 % (2.0 cm2 cell), respectively. Moreover, the devices maintained 79 % and 74 % PCE of their initial efficiency values after 2000 h of storage in ambient conditions.