Crystal structure investigation and photoluminescent aspects of green-emitting Tb3+ activated Ba2La4Zn2O10 nanocrystalline materials for solid-state illumination

Strong green emission is observed in the new Tb³⁺ activated Ba₂La₄Zn₂O₁₀ nanocrystalline material series fabricated via solution combustion methodology. A tetragonal crystal framework with space group I4/mcm (140) having irregularly shaped grains with sizes between 37 and 56 nm is formed. Morphological aspects are examined via scanning and transmission electron microscopy. On near-ultra-violet excitation, the photoluminescence spectrum presents a fair green emission at 18,348 cm⁻¹ wavenumbers consistent with the electronic transition ⁵D₄ → ⁷F₅. The energy transfer phenomena are also discussed. The highest luminous intensity is observed for 5.0 mol% of Tb³⁺ composition with 283 nm excitation wavelength. d–d exchanges authorized the presence of the concentration quenching phenomenon. Diffuse reflectance spectroscopy was taken into use to explore the energy band gap which lies in the semiconductor domain. The commission international de l’Eclairage coordinates lay in the greenish zone of the chromaticity plot, thus confirming their latent contention in phosphor-converted white light emitting diodes and advanced solid-state lighting applications.