Nature-inspired synthesis of ZrO₂:Dy³⁺ viable for WLED applications

Dy³⁺ (1 mol%)-doped zirconium oxide (ZrO₂) nanopowders were synthesized using the plant latex of Plumeria rubra. The effect of a certain amount of plant latex on the chemical composition, crystal structure and photoluminescence properties of the nanophosphors was investigated. Crystalline structure and size was analysed using XRD spectra, while TEM was taken as a supporting evidence for the particle size calculated using XRD. The band gap of the samples was obtained from Wood and Tauc plot. Scanning electron microscopy analysis reveals the formation of porous powders with a large amount of voids. Room temperature photoluminescence shows visible luminescence of the phosphors under near UV excitation. Furthermore, latex volume influences the PL emission intensity to a great extent. The colour purity of the phosphors was confirmed by Commission Internationale de l'Eclairage (CIE) coordinates. Thermoluminescence studies revealed variation in TL intensity with change in the latex volume used for preparation. TL intensity variation revealed a linear response for a dose range of 1-5 kGy of γ-ray irradiation. This study demonstrates an efficient and simple procedure for the preparation of novel colour tuneable nanophosphors suitable to be used in white light-emitting LEDs and an efficient TL dosimetric material. (orig.)