Photophysics of Atomically Thin Freestanding β-Ga 2 O 3 Nanosheets: Implications for Luminescent Thermometry

ACS Applied Nano Materials 2026

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Authors: Curtis P. Irvine, Amar K. Salih, Aviraj Ingle, Sanje Mahasivam, Bruce Cowie, Matthew R. Phillips, Vipul Bansal, Cuong Ton‐That
DOI: 10.1021/acsanm.6c01440
Cited by: 1
References: 29

Abstract

Atomically thin non-van der Waals oxides are difficult to access because strong 3D bonding resists exfoliation. Here we report an amine-assisted liquid-phase exfoliation that produces freestanding β-Ga 2 O 3 nanosheets only 2.1–2.4 nm thick with lateral sizes up to ∼10 μm, while preserving the monoclinic β-phase and a bulk-like bandgap of 4.79 ± 0.10 eV. Temperature-dependent luminescence reveals emergent 2D photophysics: self-trapped-hole emission dominates at low temperature, whereas a 2.4 eV green band exhibits negative thermal quenching from 80 to 200 K, consistent with self-trapped-hole migration to near-surface gallium-vacancy centers and highlighting opportunities for luminescent thermometry and optical sensing.

Fields of Study & Subjects

Ga2O3 and related materials GaN-based semiconductor devices and materials Transition Metal Oxide Nanomaterials

Publication details

Journal / source
ACS Applied Nano Materials
Publisher
American Chemical Society (ACS)
Volume
9
Issue
22
Pages
10019–10026
Publication date
27 May 2026
Language
EN