Enhanced Emission of Tellurite Glass Doped with Pr 3+ /Ho 3+ and Their Applications.

The shielding and spectroscopic properties of Pr ^{+ 3} and Pr³⁺/Ho³⁺-codoped tellurite glass were investigated. The intensity parameters (Ω2 = 3.24-, Ω4 = 1.64-, Ω6 = 1.10 × 10⁻²⁰ cm²) as well as the radiative lifetimes of ³F₄ + ⁵S₂ and ⁵I₆ excited states of Ho³⁺ ions were equal to 301 μs and 3.0 μs, respectively. The former value appears to be much higher than that obtained from the lifetime measurement, indicating the presence of various energy transfer processes. The NIR spectrum of Pr³⁺/Ho³⁺-co-doped tellurite glass is dominated by strong Ho³⁺: ⁵I₆ emission at around 1200 nm, being the result of the energy transfer from Pr³⁺ to Ho³⁺ ions. The shielding effectiveness of the prepared glasses showed good performance against high-energy photons. These findings suggest that the prepared glasses could be used in laser technology such as photodynamic therapy (PDT) treatment procedures and as shielding for radiation protection. [ABSTRACT FROM AUTHOR]