Optical and EPR studies of zinc phosphate glasses containing Mn2+ ions

Author(s)

Franco, Douglas F. ; Manzani, Danilo ; Carvajal, Eduar E. ; Prando, Gabriela Augusta ; Donoso, Jose Pedro ; Magon, Claudio J. ; Antonio, Selma G. ; Gobato, Yara Galvao ; Nalin, Marcelo

• Document type: Journal article
• Source: Journal of Materials Science; v. 55, n. 23, p. 14-pg., 2020-05-05.

Abstract

A set of glass samples with composition based on ternary 50P(2)O(5)-30Na(2)O-20ZnO (PNZ) matrix doped with different MnO contents was prepared via melt-quenching technique. Thermal, structural and spectroscopic properties were investigated by differential scanning calorimetry (DSC), X-ray powder diffraction (XRD), Raman spectroscopy, UV-visible absorption, photoluminescence (PL) and by electron paramagnetic resonance (EPR) using Mn2+ as probe. Glass compositions (100-x)PNZ:xMn (0.01 <= x <= 1.0 in mol% of MnO) were characterized as glasses after careful analysis of the thermal and structural data. While DSC curves show the presence of the glass transition phenomenon (T-g), XRD analysis identified the non-crystalline arrangement, compatible with glass structure. Raman spectra of PNZ:xMn samples showed that the successive increase in Mn2+ content leads to rise of vibrational modes assigned to phosphate Q(1) units, suggesting the breakdown of phosphate glass network chains. UV-Vis absorption spectra of glasses presented absorption bands centered at 250, 318, 341, 358 and 408 nm attributed to the Mn2+ electronic transitions. Glass samples containing above 0.06 mol% of MnO presented a broadband absorption centered at 511 nm assigned to the presence of traces of Mn3+. Additionally, UV-Vis, PL and EPR data showed that Mn2+ ions are occupying octahedral arrangements. Besides, EPR results suggest that the increase in MnO concentration influences on the EPR signal and hyperfine splitting constant suggests the presence of a moderately ionic bond between Mn2+ and PNZ glass network. (AU)

• FAPESP's process: 16/16900-9 - Preparation of heavy metal oxide glasses fibers with optical and magneto-optical properties
• Grantee: Douglas Faza Franco
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/16126-7 - Optically active glasses for photonic applications: synthesis, characterization and applications of quantum dots embedded in oxide glasses.
• Grantee: Danilo Manzani
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/07793-6 - CEPIV - Center for Teaching, Research and Innovation in Glass
• Grantee: Edgar Dutra Zanotto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 16/10668-7 - Optical and Transport Properties of two-dimensional semicondutors based on transition metal dichalcogenides
• Grantee: Yara Galvão Gobato
• Support Opportunities: Regular Research Grants