Investigation of structural, luminescence, and anti-bacterial properties of novel Zn1−xEuxAl2−yO4Sry phosphor.

In this research work, we synthesized novel zinc aluminate (Zn_1−xEu_xAl_2−yO₄Sr_y) sky bluish phosphors at 500 °C via the combustion route method, and for better crystallinity, we were annealed in condensing envelope with 85% of N₂ and 15% of H₂ at 1200 °C. The spinel cubic phase, elemental mapping elements, surface morphology, and vibrational properties were observed by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier Transform Infrared), and Raman spectroscopic techniques, respectively. The photoluminescence (PL) spectra were monitored by λ_ex. = 490 nm (excitation wavelength) and λ_em. = 392 (emission wavelength). Due to Eu²⁺ ions at 490 nm, intense photoluminescence spectra have been found. The PL efficiency has been found for synthesized Zn_0.95Eu_0.05Al_1.95O₄Sr_0.05 (ZAS-5) phosphor at around 93.2%. The high Corelated Color Temperature (~ 25,963 K), low color purity (50%), and low Color Rendering Index (~ 44) value were found for the ZAS-5 sample, that result (temperature) is indicating the prepared phosphor is emitting cold sky bluish light which may be useful for a sleeping light lamp, activation of photosynthesis reaction for crops, and background color for the display screen, because it may be a low dangerous color for human eyes. Antibacterial activity of phosphors indicated that combustion derived synthesized all ZAS samples may behave just like as an eco-material. [ABSTRACT FROM AUTHOR]