Enhanced Electron Extraction in Co-Doped TiO2 Quantified by Drift-Diffusion Simulation for Stable CsPbI3 Solar Cells
Abstract
Solar cells based on inorganic perovskite CsPbI3 are promising candidates to resolve the challenge of operational stability in the field of perovskite photovoltaics. For stable operation, however, it is crucial to thoroughly understand the extractive and recombinative processes occurring at the interfaces of perovskite and the charge-selective layers. In this study, we focus on the electronic properties of (doped) TiO2 as an electron-selective contact. We show via KPFM that co-doping of TiO2 with Nb(V) and Sn(IV) reduces the materials work function by 270 meV, giving it stronger n-type characteristics compared to Nb(V) mono-doped TiO2. The altered electronic alignment with CsPbI3 translates to enhanced electron extraction, as demonstrated with ssPL, trPL and trSPV in triad. Importantly, we extract crucial parameters, such as the concentration of extracted electrons and the interface hole recombination velocity, from the SPV transients via 2D drift-diffusion simulations. When implementing the co-doped TiO2 into full n-i-p solar cells, the operational stability is enhanced to 32000 h of projected TS80 lifetime. This study provides fundamental understanding of interfacial charge extraction and its correlation with operational stability of perovskite solar cells, which can be transferred to other charge-selective contacts.
Cite
@article{arxiv.2403.11982,
title = {Enhanced Electron Extraction in Co-Doped TiO2 Quantified by Drift-Diffusion Simulation for Stable CsPbI3 Solar Cells},
author = {Thomas W. Gries and Davide Regaldo and Hans Koebler and Titan Noor Hartono Putri and Gennaro V. Sannino and Emilio Gutierrez Partida and Roberto Felix and Elif Huesam and Ahmed Saleh and Regan G. Wilks and Zafar Iqbal and Zahra Loghman Nia and Florian Ruske and Martin Stolterfoht and Dieter Neher and Marcus Baer and Stefan A. Weber and Paola Delli Veneri and Philip Schulz and Jean-Baptiste Puel and Jean-Paul Kleider and Qiong Wang and Eva Unger and Artem Musiienko and Antonio Abate},
journal= {arXiv preprint arXiv:2403.11982},
year = {2025}
}
Comments
20 pages, 2 figures