Lead halide perovskites have prompted great interest, offering impressive photovoltaic performances. Most fundamental investigations and cell optimizations focus on solution-based solar cells, which are not easily extended to larger scales. Commonly in these cells, losses in the open-circuit voltage are attributed to arise primarily from interface recombination, and therefore the most studies have focused on optimization of the surface to eliminate defects states. In contrast, thermal evaporation is an alternative, solvent-free, and scalable method to deposit lead halide perovskites that is gaining attention. However, the number of reports showing high-efficiency solar cells (> 20%) prepared using thermal evaporation is still small. Here, the origins of non-radiative charge carrier recombination are investigated in perovskite cells that are deposited via thermal co-evaporation. This is done through a combination of photoluminescence spectroscopy, current-voltage characterization, and simulations. It is found that the non-radiative recombination in these cells is caused equally by bulk and interface defects. In general, it is advocated to perform a dual analysis of the photoluminescence spectroscopy of both the film and the photovoltaic device, in conjunction with current-voltage measurements. It is emphasized that such a dual analysis is needed to enable the identification of improvements and to unlock further advancements in this technology.
Bibliographical noteKAUST Repository Item: Exported on 2023-09-18
Acknowledged KAUST grant number(s): OSR-CARF/CCF-3079
Acknowledgements: The authors thank Thomas Kirchartz (Forschungszentrum Jülich) for the valuable comments on the analysis of the TRPL data. C.D. acknowledges the support of the fellowship from “la Caixa” Foundation (ID 100010434).The fellowship code is LCF/BQ/DI19/11730020. Authors acknowledge support from the Comunit at Valenciana (project CISEJI/2022/43) and the financial support of the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program(Grant Agreement No.834431). Authors acknowledge also support by the Ministry of Science and Innovation (MCIN) and the Spanish State Research Agency (AEI): grant IJCI-2019-039851-I and project CEX2019-000919-M funded by MCIN/AEI/10.13039/501100011033; grant IJC2020-045130-I funded by MCIN/AEI/10.13039/501100011033 and by the “European Union Next Generation EU/PRTR”; grants RYC-2016-21316 andRYC2019-027187-I funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in Your Future”; project PID2021-126444OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Eu-rope”. The authors acknowledge support from the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No: OSR-CARF/CCF-3079.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics