Tetrafluoroborate-Induced Reduction in Defect Density in Hybrid Perovskites through Halide Management

Tetrafluoroborate-Induced Reduction in Defect Density in Hybrid Perovskites through Halide Management

© 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 33(2021), 32 vom: 24. Aug., Seite e2102462
1. Verfasser: Nagane, Satyawan (VerfasserIn)
Weitere Verfasser: Macpherson, Stuart, Hope, Michael A, Kubicki, Dominik J, Li, Weiwei, Verma, Sachin Dev, Ferrer Orri, Jordi, Chiang, Yu-Hsien, MacManus-Driscoll, Judith L, Grey, Clare P, Stranks, Samuel D
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2021
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article charge-carrier recombination defects perovskite solar cells photoluminescence surface treatment tetrafluoroborate
Beschreibung
Zusammenfassung:© 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH.
Hybrid-perovskite-based optoelectronic devices are demonstrating unprecedented growth in performance, and defect passivation approaches are highly promising routes to further improve properties. Here, the effect of the molecular ion BF4 - , introduced via methylammonium tetrafluoroborate (MABF4 ) in a surface treatment for MAPbI3 perovskite, is reported. Optical spectroscopy characterization shows that the introduction of tetrafluoroborate leads to reduced non-radiative charge-carrier recombination with a reduction in first-order recombination rate from 6.5 × 106 to 2.5 × 105 s-1 in BF4 - -treated samples, and a consequent increase in photoluminescence quantum yield by an order of magnitude (from 0.5 to 10.4%). 19 F, 11 B, and 14 N solid-state NMR is used to elucidate the atomic-level mechanism of the BF4 - additive-induced improvements, revealing that the BF4 - acts as a scavenger of excess MAI by forming MAI-MABF4 cocrystals. This shifts the equilibrium of iodide concentration in the perovskite phase, thereby reducing the concentration of interstitial iodide defects that act as deep traps and non-radiative recombination centers. These collective results allow us to elucidate the microscopic mechanism of action of BF4 -
Beschreibung:Date Revised 13.10.2024
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.202102462