@article{b4a16ee5043f474e9dbdcf28e6992d74,
title = "LiI doping of mixed-cation mixed-halide perovskite solar cells: defect passivation, controlled crystallization and transient ionic response",
abstract = "We investigate lithium iodide (LiI) doping of mixed-cation mixed-halide (MCMH) perovskites as a method to improve film morphology and optoelectronic properties, reduce defect-related recombination losses and limit ion migration. The optimized Li-doped devices achieved 21.5% power conversion efficiency (PCE) compared to 20.4% for undoped control devices. Furthermore, optimized Li-doped devices show minimized current-voltage hysteresis across a wide range of scan rates compared to control devices, which displayed significant scan-rate dependent hysteresis. We show, using a combination of experimental analysis and numerical device simulations, that the improved device performance and transient response at optimum doping concentration are consistent with reduced non-radiative recombination in the perovskite. However, increasing the LiI dopants beyond the optimum concentration alters the ionic properties of the perovskite absorber and changes the transient response. We also find that LiI addition results in a downward shift of the valence band and a corresponding transition from a weakly n-type to p-type perovskite material. These findings reveal the beneficial role of LiI dopant at low concentrations can improve shelf-life and minimize recombination-active defects, which are favourable for designing high-performance and stable mixed-cation mixed-halide perovskite devices.",
keywords = "Crystallization, Defect passivation, Hysteresis, ion migration, Mixed-cation mixed-halide perovskite, Recombination, Transient response",
author = "Tabi, {G. D.} and Pham, {H. T.} and H. Zhan and D. Walter and Mayon, {A. O.} and J. Peng and T. Duong and Shehata, {Mohammed M.} and H. Shen and L. Duan and N. Mozaffari and L. Li and Mahmud, {M. A.} and Nguyen, {H. T.} and K. Weber and Catchpole, {K. R.} and White, {T. P.}",
note = "Funding Information: The work was supported by the Australian Government through the Australian Renewable Energy Agency (ARENA) and the Australian Research Council (ARC). T.P.W. is the recipient of an Australian Research Council Australian Future Fellowship (project number FT180100302) funded by the Australian Government. H.T.N. acknowledges a fellowship support from the Australian Centre for Advanced Photovoltaics (ACAP). Responsibility for the views, information, or advice herein is not accepted by the Australian Government. Part of the experiments were conducted at the ACT Node of the Australian National Fabrication Facility (ANFF @ ANU), the Australian Microscopy and Microanalysis Research Facility (AMMRF) at the Centre for Advanced Microscopy (CAM @ ANU) and the surface analysis laboratory (SSEAU @ MWAC, UNSW). The authors also acknowledge supports from an Infrastructure Fund from the ACAP. Funding Information: The work was supported by the Australian Government through the Australian Renewable Energy Agency (ARENA) and the Australian Research Council (ARC). T.P.W. is the recipient of an Australian Research Council Australian Future Fellowship (project number FT180100302 ) funded by the Australian Government . H.T.N. acknowledges a fellowship support from the Australian Centre for Advanced Photovoltaics (ACAP). Responsibility for the views, information, or advice herein is not accepted by the Australian Government. Part of the experiments were conducted at the ACT Node of the Australian National Fabrication Facility (ANFF @ ANU), the Australian Microscopy and Microanalysis Research Facility (AMMRF) at the Centre for Advanced Microscopy (CAM @ ANU) and the surface analysis laboratory (SSEAU @ MWAC, UNSW). The authors also acknowledge supports from an Infrastructure Fund from the ACAP . Publisher Copyright: {\textcopyright} 2022 Elsevier Ltd",
year = "2022",
month = oct,
doi = "10.1016/j.mtphys.2022.100822",
language = "English",
volume = "27",
journal = "Materials Today Physics",
issn = "2542-5293",
publisher = "Elsevier",
}