Optical characterization and defect-induced behavior in ZnAl1.999Ho0.001O4 spinel: unraveling novel insights into structure, morphology, and spectroscopic features

The ZnAl1.999Ho0.001O4 phosphor, prepared by the solid-state method, crystallizes in the cubic spinel structure. Morphology and chemical composition homogeneity were determined via Energy Dispersive X-ray and SEM analysis. The (Eg) optical band gap was evaluated from the UV/vis absorption spectrum,...

Full description

Bibliographic Details
Authors: Elhamdi, I.; Souissi, H.; Taktak, O.; Kammoun, S.; Dhahri, E.; Pina, J.; Costa, B.F.O.; López Lago, María Elena
Format: Article
Publication date:2024
Country:España
Institution:Universidad de Santiago de Compostela (USC)
Repository:Minerva. Repositorio Institucional de la Universidad de Santiago de Compostela
Language:English
OAI Identifier:oai:minerva.usc.gal:10347/43043
Online Access:https://hdl.handle.net/10347/43043
Access Level:Open access
Keyword:ZnAl1.999Ho0.001O4 spinel
Raman
FTIR
UV/Vis spectroscopy
Lanthanide
Description
Summary:The ZnAl1.999Ho0.001O4 phosphor, prepared by the solid-state method, crystallizes in the cubic spinel structure. Morphology and chemical composition homogeneity were determined via Energy Dispersive X-ray and SEM analysis. The (Eg) optical band gap was evaluated from the UV/vis absorption spectrum, confirming direct transition behavior according to Tauc’s law. The Urbach energy (Eu) in the ZnAl1.999Ho0.001O4 spinel was higher than that in the ZnAl2O4 spinel, indicating increased disorder and a higher concentration of defects due to Ho3+ ions. The penetration depth (δ(λ)), optical extinction (k(λ)), and refractive index (n(λ)) were assessed across wavelengths (λ). The room temperature absorption spectrum revealed several peaks corresponding to the 4f-4f transitions of Ho3+ ions.