Energy transfer from Gd³⁺ to Eu³⁺ in silica xerogels

Luminescent xerogels co-doped with Gd³⁺ and Eu³⁺ ions were obtained in silica matrix. The effect of gadolinium ions on visible emission of europium ions in prepared xerogels has been studied. Spectroscopic parameters for Eu³⁺ and Gd³⁺ ions were determined based on excitation and emission measurements as well as luminescence decay analysis. The luminescence decay for the ⁵D₀ level of Eu³⁺ ions in sample after excitation at 273 nm is almost twice as long in comparison to excitation at 393 nm. The luminescence intensity coefficient R (Eu³⁺) was calculated, and it was found that ratio of the intensity of red to orange line clearly depends on the excitation parameters. Based on these spectroscopic parameters the energy transfer process from Gd³⁺ to Eu³⁺ ions has been confirmed. - Highlights: • Sol–gel systems co-doped with Gd³⁺/Eu³⁺ ions have been fabricated. • Spectroscopic parameters for Eu³⁺were detected under different excitation wavelengths. • Efficient energy transfer from Gd³⁺ to Eu³⁺ ions was confirmed