Synthesis of down conversion, high luminescent nano-phosphor materials based on new developed Ln3+:Y2Zr2O7/SiO2 for latent fingerprint application

New down-converting materials based on lanthanide doped yttrium zirconate nanoparticles impeded in silica matrix (x mol% Ln3+:Y2Zr2O7/SiO2 (LnYZS) where (Ln3+=Eu3+, Tb3+, Sm3+, Dy3+ or Pr3+; x=4, 17 and 35 mol%) and YZS=Y2Zr2O7/SiO2) were synthesized by sol–gel process followed by thermal treatment at 1100 °C for 8 h. The LnYZS nano-phosphors were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive X-ray (EDS), FT-IR and photoluminescence (PL) spectroscopy. The prepared nano-phosphor materials had a well crystalline structure with nano-size spherical morphology and exhibited an enhanced emission with different colors in the visible range depending on the type of Ln3+ ion due to different transition mechanisms. The longest PL was detected for EuYZS and TbYZS nano-phosphors which were characterized by highly pure red and green fluorescence, respectively. The PL properties of EuYZS and TbYZS nano-phosphors make them promising materials for finger print detection application. The fingerprint details on different nonporous surfaces (glass, aluminum foil, CD and plastic bag) were clearly developed with EuYZS and TbYZS nano-phosphors under UV illumination.