Effective energy transfer from Dy3+ to Tb3+ ions in thermally stable KZABS glasses for intense green emitting device applications

Abstract Potassium Zinc Alumino Borosilicate (KZABS) glasses co-doped with Dy3+/Tb3+ ions have been synthesized by employing a sudden melt quenching technique. To check the luminescence behavior, the as prepared glasses were characterized by employing spectroscopic tools like photoluminescence (PL) excitation and emission, temperature dependent PL and PL decay to see the energy transfer between Dy3+ and Tb3+ ions and optimum green emission suitable for photonic applications. The XRD spectra reveals the amorphous nature of the as prepared KZABS glasses. PL spectral features show optimum green emission and confirms energy transfer from Dy3+ to Tb3+ ions. With the help of temperature dependent PL, glasses were found to be thermally stable. The decay profiles recorded show bi-exponential nature and demonstrates the energy transfer that took place from Dy3+ to Tb3+ ions. The Inokuti- Hirayama (I–H) model confirms the interaction involved in energy transfer process as dipole-dipole in nature. The CIE coordinates are found to be shifting gradually towards intense green region with increase in activator concentration (Tb3+) under the optimized sensitizer (Dy3+) concentration. It is also observed that, the CIE coordinates shifting towards intense green region when the as prepared KZABS glasses are excited with suitable excitation wavelengths of both sensitizer and activator. All the studies finally reveal the superiority of Dy3+/Tb3+ co-doped KZABS glasses for their usage in green emitting photonic device applications such as w-LEDs and display devices.