Two-step spin-coating of vacancy-ordered double perovskites enables growth of thin films for electronic devices

TitleTwo-step spin-coating of vacancy-ordered double perovskites enables growth of thin films for electronic devices
Publication TypeJournal Article
Year of Publication2025
AuthorsKuklinski, Owen, Alexandra Brumberg, Linjing Tang, Anya S. Mulligan, Tim Kodalle, Carolin M. Sutter-Fella, Ram Seshadri, and Michael L. Chabinyc
JournalJournal of Materials Chemistry C
Volume13
Start Page11402
Issue13
Pagination11402-11412
Date Published05/2025
Abstract

Vacancy-ordered double perovskites (VODPs), such as Cs2TeX6 (X = Cl, Br, I), are lead-free alternatives to conventional metal-halide perovskites (MHPs). One limitation of VODPs is the lack of processes to form thin films relevant for physical characterization and electronic devices. A two-step spin-coating method was developed for synthesizing high-quality films of Cs2TeBr6. Independently depositing CsBr and TeBr4 enables high precursor concentrations and control over crystallization kinetics. By optimizing the spin-coating parameters, conversion of precursors to phase pure films was observed using structural and surface characterization methods. The growth of mixed-halide systems was investigated using alternative salts including CsCl and CsI. The formation of halide alloys was found to depend on the existence of routes to byproducts. Lastly, single carrier diodes of Cs2TeBr6 were designed following valence band characterization with photoelectron spectroscopy. Temperature-dependent space-charge-limited current measurements revealed that transport occurs by hopping and the hole mobility is 3.2 × 10−5 cm2 V−1 s−1 near room temperature. The insights from the 2-step procedure provide a pathway towards making semiconducting devices from VODPs.

URLhttps://pubs.rsc.org/en/content/articlehtml/2025/tc/d5tc00502g
DOI10.1039/D5TC00502G