Strongly Fluorescent Blue-Emitting LaO: Bi Phosphor for Latent Fingerprint Detection.

Blue-emitting bismuth-doped lanthanum oxide (LaO: Bi) with various concentrations of Bi was synthesized using the sol-gel combustion method and used for visualization of latent fingerprints (LFPs). An X-ray diffraction (XRD) study revealed the hexagonal structure of the phosphors and total incorporation of the bismuth in the LaO matrix. Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared Spectroscopy (FTIR) were used to study the morphology and the relative vibrations of the synthesized samples.