Correlation between native defects and dopants in colloidal lanthanide-doped Ga2O3 nanocrystals: A path to enhance functionality and control optical properties

Ting Wang, Arunasish Layek, Ian D. Hosein, Vadim Chirmanov, Pavle V. Radovanovic

Research output: Contribution to journalArticle

21 Scopus citations

Abstract

We report the synthesis and study of the photoluminescence properties of colloidal lanthanide(iii)-doped Ga2O3 nanocrystals. The Ga2O3 nanocrystal host lattice acts as a sensitizer of the Eu3+ dopant red emission arising from intra-4f orbital transitions, and concurrently exhibits a strong blue photoluminescence originating from defect-based donor-acceptor pair (DAP) recombination. The Eu3+ sensitization, enabled by the energy transfer from the nanocrystal host lattice to the dopant centers, allows for the generation of dual blue-red emission. Increasing doping concentration leads to a decrease in the donor activation energy allowing for simultaneous control of the optical and electrical properties of these multifunctional nanocrystals. Analyses of the steady-state and time-resolved photoluminescence spectra suggest that Eu3+ ions occupy at least two different sites, which were tentatively designated as the six-coordinate internal and surface-related dopants. Uniquely, both DAP and Eu3+ emissions have long lifetimes (in milliseconds), although Eu3+ luminescence has a slower decay rate. These phenomena enable a temporal modulation of the dual emission and photoluminescence chromaticity on the millisecond timescale. The generality of these findings was demonstrated by preparing Tb3+-doped Ga2O3 nanocrystals, as a blue-green dual emitter. Owing to their optical transparency, electrical properties, emission color versatility, robustness, and fabricability, colloidal lanthanide(iii)-doped Ga2O3 nanocrystals are a promising class of multifunctional materials and complex phosphors. This journal is

Original languageEnglish (US)
Pages (from-to)3212-3222
Number of pages11
JournalJournal of Materials Chemistry C
Volume2
Issue number17
DOIs
StatePublished - May 7 2014
Externally publishedYes

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Correlation between native defects and dopants in colloidal lanthanide-doped Ga<sub>2</sub>O<sub>3</sub> nanocrystals: A path to enhance functionality and control optical properties'. Together they form a unique fingerprint.

  • Cite this