One pot synthesis of TiO2: Eu3+ hierarchical structures as a highly specific luminescent sensing probe for visualization of latent fingerprints

Abstract

In the present work, TiO2:Eu3+ (1 mol%–11 mol%) nano powders (NPs) were prepared via a facile one-pot hydrothermal method by using Epigallocatechin Gallate (EGCG) as biosurfactant. The optimized TiO2:Eu3+ (5 mol%) NPscan be used as fluorescent labeling agent for visualizing of latent fingerprints (LFPs) on various porous and non-porous surfaces. The obtained results exhibit well defined ridge details with high sensitivity, selectivity, and low background hindrance which show greater advantages as compared to conventional powders. We demonstrate the viability of high-performance security labels thorough excellent luminescence for practical anti-mimetic applications. Morphology of the prepared samples were highly dependent on pH, concentration of the bio-surfactant, temperature and time durations. Photoluminescence (PL) emission spectra exhibit intense red emission at ~ 615 nm due to electric dipole transition (5D0→7F2). Photometric (CIE and CCT) results clearly show the intense warm red emission of the optimized samples. Therefore, this work offers a superior and universal luminescent label, which can be applied to visualize miniature LFPs particulars for individualization and consequently display great prospective in forensic investigation.