Excitation Management of Lead-Free Perovskite Nanocrystals Through Doping

Despite their low toxicity and phase stability, lead-free double perovskite nanocrystals, Cs2AgInCl6 in specific, have suffered from low quantum yield of photoluminescence. This is mainly due to two reasons, including (i) the quenching effect from metal silver which was usually formed at high temperature from Ag+ reduction in the presence of organic amines and (ii) the parity-forbidden transition of pristine double perovskites. Here, we reported a room-temperature synthesis of Cs2AgInCl6 nanocrystals in an inverse microemulsion system, where Ag+ reduction was largely suppressed. By codoping Bi and Na ions, dark self-trapping excitons (STEs) were converted into bright ones, enabling a bright phosphor of photoluminescence quantum yield up to 56%. Importantly, the doping approach at room temperature relaxed the parity-forbidden transition (1S0 → 3P2) of Bi-6s2 orbitals, revealing a fine structure of a triband excitation profile. Such spin-rule relaxation was ascribed to symmetry breaking of the doped lattice, which was evidenced by Raman spectroscopy. In a proof-of-concept experiment, the bright nanocrystals were used as a color-converting ink, which enabled a stable white light light-emitting diode to operate in various environments, even under water, for long-term service.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:13

Enthalten in:

ACS applied materials & interfaces - 13(2021), 5 vom: 10. Feb., Seite 6404-6410

Sprache:

Englisch

Beteiligte Personen:

Zheng, Wei [VerfasserIn]
Sun, Ruijia [VerfasserIn]
Liu, Yeqi [VerfasserIn]
Wang, Xiaojia [VerfasserIn]
Liu, Nianqiao [VerfasserIn]
Ji, Yanchen [VerfasserIn]
Wang, Liangling [VerfasserIn]
Liu, Hong [VerfasserIn]
Zhang, Yuhai [VerfasserIn]

Links:

Volltext

Themen:

Doped perovskite
Excitation spectrum
Journal Article
Lead-free perovskite
Parity-forbidden
Self-trapped exciton

Anmerkungen:

Date Revised 11.02.2021

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1021/acsami.0c20230

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM320614387