Fluorinated Interlayer Modulation of NiOx-Based Inverted Perovskite Solar Cells

p-Type inorganic nickel oxide (NiOx) exhibits high transparency, tunable-optoelectronic properties, and a work function (WF) that is potentially suitable for hole extraction in inverted perovskite solar cells (PSCs). However, NiOx films possess surface defects that lead to high interfacial recombination and an energy offset with the ionization potential of the perovskite. Herein, we show that fluorinated 3-(2,3,4,5,6-pentafluorophenyl)propan-1-aminium iodide (FPAI) can be used to modify the electronic properties of the NiOx anode interlayer. The FPAI modification led to good perovskite crystal growth and films with reduced surface defects. The FPAI modification also increased the WF of NiOx and improved charge extraction. These improvements led to an increased Voc value compared with control devices without FPAI modification, 1.05 V versus 1.00 V, and a higher short-circuit current and larger fill factor. As a result, the best PSCs with FPAI-modified NiOx had a power conversion efficiency of 19.3%. Finally, the PSCs with the FPAI-modified NiOx layer were found to have improved stability.

Citation

Li, H., Bati, A. S. R., Chu, R., Zhang, G., Li, Y., Lin, Q., Burn, P. L., Shaw, P. E., & Gentle, I. R. (2022). Fluorinated Interlayer Modulation of NiOx-Based Inverted Perovskite Solar Cells. ACS Applied Materials & Interfaces. https://doi.org/10.1021/acsami.2c11082

Sponsors

A.S.R.B. acknowledges support from King Abdullah University of Science and Technology (KAUST) through the Ibn Rushd Postdoctoral Fellowship Award. The authors acknowledge the facilities and the scientific and technical assistance of the Queensland node of the Australian National Fabrication Facility (ANFF) and Microscopy Australia at the Centre for Microscopy and Microanalysis, The University of Queensland. This program has been supported in part by the Australian Government through the Australian Renewable Energy Agency (ARENA) Australian Centre for Advanced Photovoltaics. Responsibility for the views, information or advice expressed herein is not accepted by the Australian Government. P.L.B. is a University of Queensland Laureate Fellow.