Formation of mechanism and excitonic luminescence of supercritical-fluid-synthesized ZnO nanoparticles
Language
en
Article de revue
This item was published in
Chemistry of Materials. 2023, vol. 35, n° 10, p. 4057–4067
American Chemical Society
English Abstract
Extensive research on nanosized ZnO has proven that its optical properties are challenging to control due to a number of possible defects producing various emissions in the visible range. Our group proposed a low-temperature, ...Read more >
Extensive research on nanosized ZnO has proven that its optical properties are challenging to control due to a number of possible defects producing various emissions in the visible range. Our group proposed a low-temperature, supercritical-fluid-driven synthesis of isotropic nanosized particles that exhibit a unique and unprecedentedly pure excitonic emission, comparable to that of single crystals. The present article reports the growth mechanism at the origin of the unexpectedly pure excitonic emission as well as a more detailed study of its optical properties at liquid helium temperatures. The ZnO phase is obtained via the thermal decomposition of an intermediate ZnO2 phase. No bulk defect luminescence is detected, and the synthesis route leaves a “ZnO2-like” surface able to neutralize the formation of surface defects, which can contribute to visible emissions. The luminescence measurements were performed at liquid helium temperature to enable the identification of excitons. The investigation of the photoluminescence properties confirms a strong excitonic emission in the UV region with no visible band and sheds light on a phonon coupling with the E2 high vibrational mode.Read less <
English Keywords
Crystal structure
Excitons
Metal oxide nanoparticles
Nanoparticles
Oxides
ANR Project
Initiative d'excellence de l'Université de Bordeaux - ANR-10-IDEX-0003
University of Bordeaux Graduate Scholl in Light Sciences & Technologies - ANR-17-EURE-0027
University of Bordeaux Graduate Scholl in Light Sciences & Technologies - ANR-17-EURE-0027
Origin
Hal imported