Diverse crystallographic and luminescence aspects of Eu³⁺ activated new BaSrLa₄O₈ nanophosphor for progressive optoelectronic applications

Eu³⁺-activated orthorhombic BaSrLa₄O₈ nanocrystal system with strong red luminescence was prepared using the energy-saving solution combustion method. Its crystal structure is orthorhombic, it belongs to the Pnma (162) space group, and its particle shape and diameter range from 44 to 68 nm. Morphological aspects were examined by scanning and transmission electron microscopy techniques. When exposed to UV radiation, the nanocrystal emits vibrant red light with a wavenumber of 18,281 cm⁻¹ due to the change of electronic state ⁵D₀ → ⁷F₅. The effect of energy transfer is also demonstrated. The maximum emission intensity was observed at 10.0 mol% Eu³⁺ ion concentration when excited at 394 nm. This phenomenon can be attributed to the interaction-quenched d–d interaction leading to decreased luminescence intensity. According to the chromaticity diagram, the composite color falls in the red region and the relative color coordinate temperature of the optimized sample BaSrLa_3.60Eu_0.40O₈ is measured at 2234 K. These nanocrystals are especially best for producing white light emitting diodes for advanced optoelectronic applications.