Phosphorus Oxidation Controls Epitaxial Shell Growth in InP/ZnSe Quantum Dots.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39810372.
- Also identified by DOI 10.1021/acsnano.4c13110 and PMC identifier 11752496.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
InP/ZnSe/ZnS core/shell/shell quantum dots are the most investigated quantum dot material for commercial applications involving visible light emission. The inner InP/ZnSe interface is complex since it is not charge balanced, and the InP surface is prone to oxidation. The role of oxidative defects at this interface has remained a topic of debate, with conflicting reports of both detrimental and beneficial effects on the quantum dot properties. In this study we probe the structure of the InP/ZnSe interface at the atomic level using <sup>31</sup>P, <sup>77</sup>Se and <sup>17</sup>O ssNMR and HAADF-STEM. We observe clear differences in Se NMR spectra and crystal orientation of core and shell when the InP/ZnSe is oxidized on purpose. High levels of interface oxidation result in an amorphous phosphate layer at the interface, which inhibits epitaxial growth of the ZnSe shell.