ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Structural, morphological and photoluminescence properties of β-Ag₂MoO₄ doped with Eu³⁺

Priscila B. Almeida, Ivo M. Pinatti, Regiane C. de Oliveira, Mayara M. Teixeira, Clayane C. Santos, Thales R. Machado, Elson Longo, and Ieda L. V. Rosa

Chemistry Departament, CDMF, Federal University of São Carlos, São Carlos, Brazil

E-mail: ilvrosa@ufscar.br

Received: 8 July 2020  Accepted: 19 December 2020

Abstract:

In this work, we report the investigation on β-Ag_(2-3x)Eu_xMoO₄ (x = 0.0; 0.0025; 0.005; 0.0075, and 0.01 mmol) materials prepared using the coprecipitation method. X-ray diffraction (XRD), Rietveld refinement analysis, and Raman spectroscopy confirmed that all of the synthesized β-Ag_(2-3x)Eu_xMoO₄ samples were perfectly monophasic, with spinel-like cubic structure. The results obtained in the morphological analysis indicate that the insertion of the Eu³⁺ ion into the β-Ag₂MoO₄ matrix favors the formation of surface defects and suggests that in higher concentrations of dopant the particles become more geometrically defined. The photoluminescence analysis (PL) was performed using two excitation sources: krypton laser and xenon lamp. Through the emission and excitation spectra it was observed that β-Ag₂MoO₄ exhibits broad band in the blue region, and as the concentration of Eu³⁺ increases this emission is gradually suppressed, giving rise to an intense emission with narrow and well-defined lines in the red region, confirming β-Ag₂MoO₄ as a good matrix capable of sensitizing and stabilizing the red emission of the Eu³⁺ ion. In addition, all other characterizations demonstrate that the replacement of Ag⁺ by Eu³⁺ ions caused structural, morphological, and optical changes with lattice disturbances in the short, medium, and long ranges.

Keywords: Silver molybdate; Europium; Doping; Morphological analysis; Photoluminescence

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-020-01489-4

Chemical Papers 75 (5) 1869–1882 (2021)