Controlling disorder in the ZnGa2O4:Cr3+ persistent phosphor by Mg2+ substitution
Artikel i vetenskaplig tidskrift, 2017

We have studied in this work the effect of increasing structural disorder on the persistent luminescence of a Cr3+ doped zinc gallate spinel. This disorder was introduced by progressive substitution of Zn2+ by Mg2+ ions, and was studied by photoluminescence, X-ray diffraction, extended X-ray absorption fine structure (EXAFS), X-ray absorption near edge structure (XANES) and electron paramagnetic resonance (EPR) spectroscopy. It was found that increasing the Mg/Zn substitution decreases the number of Cr3+ in undistorted sites and increases the number of Cr3+ with neighbouring antisite defects and with neighbouring Cr3+ ions (referred to as Cr clusters), which in turn decreases the intensity of persistent luminescence. Both XANES and EPR spectra could be simulated by a linear combination of Cr3+ spectra with three types of Cr3+ environments. The increasing disorder was found to be correlated with a decrease of the average Cr-O bond length and a decrease of crystal field strength experienced by Cr3+ ions.


N. Basavaraju

Indian Institute of Science, Bangalore

Goa University

K. R. Priolkar

Goa University

A. Bessiere

Institut de Recherche de Chimie Paris

Suchinder Sharma

Chalmers, Fysik, Kondenserade materiens fysik

D. Gourier

Institut de Recherche de Chimie Paris

L. Binet

Institut de Recherche de Chimie Paris

B. Viana

Institut de Recherche de Chimie Paris

S. Emura

Osaka University

Physical Chemistry Chemical Physics

1463-9076 (ISSN) 1463-9084 (eISSN)

Vol. 19 1369-1377


Den kondenserade materiens fysik