Fabrication and photoluminescent features of cool-white light emanating Dy3+ doped Ba5Zn4Gd8O21 nanophosphors for near UV-excited pc-WLEDs

To enhanced the quality of multi–phase WLEDs, a down-converted trivalent dysprosium (Dy3+) activated Ba5Zn4Gd8O21 nanocrystals illuminating cool white light were manufactured via eco-friendly methodology i.e. solution combustion methodology. XRD (X-ray diffractometer) instrument and Rietvield refinement investigations over XRD data of the prepared sample discloses the 14/m (87) phase group with tetragonal symmetry in activated sample (Ba5Zn4Gd8(1-x)Dy8xO21 (x = 1.0, 3.0, 5.0, 7.0, 10.0 mol%). Morphological investigations reported the rod like crystals (35-45 nm) whereas their nano-crystalline behavior was demonstrated by SAED (selected area electron diffraction) profiles. Uniform composition of the element present in the targeted nanocrystals was accomplished via an EDAX (energy dispersive X-ray) analysis. Photoluminescence (PL) spectrum, on NUV excitation depicted two important peaks in the blue (B) & yellow (Y) region at 488 nm and 578 nm. Maximum luminescent intensity was noticed as 3.0 mol% amount of activator (Dy3+) cations. Band gap, decay life time, quantum efficiency and non radiative rates of optimal powder were found as 4.46 eV, 0.5214 ms, 65.17% and 66.79 s1, respectively. Moreover, chromaticity coordinates (0.2850, 0.3021), color purity (24.06 × 10−2) & CCT value (8910.6 K) of Ba5Zn4Gd7.76Dy0.24O21 nanocrystals were found resemblance to the coordinates of NTSE and commercial LEDs which certified their utilization in the advanced opt-electronic appliance, especially in single phased WLEDs.