Currently the traditional powder dusting method has low resolution, less sensitive, low contrast and high background noise. To provide the suitable solution for the existing problems of powder dusting method, Eu3+ doped CaZrO3 nanoparticles were prepared by a facile solution combustion method using Aloe vera gel was used as a dusting powder. Powder X-ray diffraction results showed the orthorhombic phase. Scanning electron microscopy supports for the Ostwald reopening phenomena and observed flakes type morphology. Transmission electron microscopy analysis supports for the flakes type morphology and shows the polycrystalline nature of the prepared samples. Photoluminescence studies revealed that the transitions from the excited states 5D0 to the ground state7Fj (j = 0, 1, 2, 3, 4) of Eu3+ ions. The product showed intense red light emission with the color coordinates of (0.640, 0.359). The estimated correlated color temperature value was ∼1798 K also the estimated color purity and quantum efficiency are found to be 75.79% and 74% respectively. The optimum concentration of Eu3+ ions in CaZrO3 host lattice has been found to be at 9 mol%. Using this optimized CaZrO3: Eu3+ phosphors, various ridge shapes (arch, whorl and loop) of the latent fingerprints were observed clearly. Further, under 254 nm UV and normal light illumination, on substrates (glass, aluminum foil, stainless steel, compact disk and credit card) also the visualization was excellent and sensitivity was high to see the clear ridges. The results indicate that CaZrO3: Eu3+ (9 mol%) phosphors can be effectively used in fingerprint identification, anti-counterfeiting applications and red component of WLEDs.
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