The effect of cobalt/copper ions on the structural, thermal, optical, and emission properties of erbium zinc lead borate glasses

Abstract

A host glass network of 70B2O3–10Pb3O4–18ZnO–2Er2O3 (ErCoCu1) was proposed and the impact of 1 mol% of Co or/and Cu ions on its structural, thermal, optical, and green emission properties was studied extensively. The X-ray diffraction spectra confirmed the amorphous structure of the produced glasses. Density and density-based parameters behavior showed that the Co or/and Cu ions fill the interstitial positions of the proposed ErCoCu1 network, causing its compactness. Both ATR-FTIR and Raman Spectra affirmed the formation of the fundamental structural units of the borate network, B–O–B linkage, BO3, and BO4. Additionally, the penetration of Co or/and Cu ions inside the ErCoCu1 converts the tetrahedral BO4 units to triangle BO3 causing its richness by non-bridging oxygens. The addition of Co or/and Cu reduces the glass transition temperature as a result of the conversion of the BO4 to BO3 units. Optical absorption spectra for the host glass ErCoCu1 showed many of the distinguished absorption bands of the Er3+ ion. Penetration of Co ion generates two broadbands referring to the presence of Co2+ ions in both tetrahedral and octahedral coordination and Co3+ ions in the tetrahedral coordination. In the Cu-doped glasses, the characteristic absorption bands of Cu2+ and Cu+ were observed. A green emission was generated from the ErCoCu1 glass under 380 nm excitation wavelength. Moreover, no significant effect of Co or/and Cu on the emission spectra was recorded. The considered glasses had appropriate properties qualifying them for optoelectronics and nonlinear optics applications.