Effect of Li+ codoping on structural and luminescent properties of Mg2SiO4:RE3+ (REÂ =Â Eu, Tb) nanophosphors for displays and eccrine latent fingerprint detection

Luminescent nanophosphors find wide range of applications for the fabrication of WLEDs as well as in fingerprint detection techniques. Lithium co-doped Mg2SiO4:Tb3+ and Mg2SiO4:Eu3+ nanophosphors were prepared by low temperature solution combustion method. The effect of Li+ co-doping in Mg2SiO4 was systematically studied by Powder X-ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), UV-Vis- Diffuse reflectance spectroscopy (DRS) and Photoluminescence (PL) spectroscopy. Further, the optimized powders were used to analyze the eccrine latent fingerprint. The DRS analysis show red shift of the absorption edges in Li+ co-doped nanophosphors. PL studies revealed that a small quantity of Li+ (1 mol %) ions was effective for charge compensation as well as creation of lattice defects to enhance the luminescence emission. The high quantum efficiency and color purity projects it to be a new material for commercial application in white light emitting diodes.