High-Efficiency Perovskite Solar Cell Based on Sequential Doping of PTAA

Perovskite solar cells have been extensively studied and have recently demonstrated a power conversion efficiency above 23%. In our present approach, we select poly(triaryl amine) (PTAA) as the hole-transport material and use an inverted solar cell planar structure. We propose a sequential method to dope the PTAA thin film in order to reduce the solar cell's series resistance. A modified inter-diffusion method is adopted to improve the perovskite film. We optimize the solvent-assisted annealing condition to maximize the perovskite grain size and reduce the pin-hole density. The impact of PTAA's doping concentration on the solar cell's PV performance is investigated. Compared to conventional PEDOT:PSS-based perovskite solar cell, we observe an improvement in both the open-circuit voltage and the short-circuit current, resulting in a power conversion efficiency enhancement from 12.7% to 15.3%.