Interplay between structural modifications and optical/luminescence response in Mn-doped alkali borate glasses

Novel alkali-borate glass system with the compositions [20 Na2O - 10 ZnO - (70 -x) B2O3 - x MnO2 (x varies from 1.0 to 6.0 mol%)] has been produced by the melt quenching technique. The impacts of MnO2 dopant on the structural, optical and luminescence features of the prepared samples were investigated by a set of commentary techniques. The structural characterizations inferred from XRD, density, and FTIR analysis verified the amorphous nature of the produced samples and the entry of manganese ions as a network modifier, where the density increased, and the proportion of non-bridged oxygen grew due to the structural conversions between the tetrahedral and triangular units. Optical absorption spectra revealed a progressive increase in the concentrations of Mn3+/Mn2+ ions occupying tetrahedral and/or octahedral sites, while luminescence properties confirmed the role of Mn2+ ions in obtaining the deep red emission at similar to 698-701 nm. Structural modifications supported the growth of linear and nonlinear refractive indices and the successive decrease in the band gap energy from 3.33 to 3.10 eV with a rising of Urbach energy. The metallization criterion of the produced samples ranged from 0.408 to 0.394 eV(-1), confirming the semiconductor behavior of these samples. The ESR results were in good agreement with the Mn2+ ligand field effect, verifying the covalent bonding nature of these ions with their tendency to occupy more octahedral sites. The explored properties of the present glass compositions qualify their utilization as optically active materials in multifunctional optical and optoelectronic devices operating in visible spectral systems.

Automated summary

A novel alkali-borate glass system with different concentrations of MnO2 was produced using the melt quenching technique. The structural, optical, and luminescence properties of the glass were investigated, and the results showed potential applications in multifunctional optical and optoelectronic devices.