Europium-Doped Tellurite Glasses: The Eu²⁺ Emission in Tellurite, Adjusting Eu²⁺ and Eu³⁺ Emissions toward White Light Emission

Europium-doped magnesium tellurite glasses were prepared using melt quenching techniques and attenuated total reflection (ATR) spectroscopy was used to study the glass structure. The glass transition temperature increased with increasing MgO content. Eu²⁺ and Eu³⁺ emissions were studied using photoluminescence spectroscopy (PL). The broad emission of Eu²⁺ ions centered at approximately 485 nm was found to decrease in intensity with increasing MgO content, while the Eu³⁺ emission was enhanced. The Eu³⁺ emission lay within the red orange range and its decay time was found to increase with increasing MgO content. Different excitation wavelengths were used to adjust Eu²⁺ to Eu³⁺ emissions to reach white light emission. The white light emission was obtained for the sample with the lowest MgO content under excitation in the near-UV range.