Phytochemical mediated synthesis of praseodymium doped beta-eucryptite nanophosphor for ultraviolet stimulated fluorescence based unclonable security applications

Abstract

Herein, we reported the preparation of orange-red emitting Pr3+ (1–11 mol %) doped beta-eucryptite (LiAlSiO4) nanophosphors via a simple low-temperature solution combustion method. The prepared beta-eucryptite revealed hexagonal crystal structure. The Pr3+doped beta-eucryptitedisplays broad emission peak at 608 nm along with a weak intensive peak at 632 nm ascribed to1D2→3H4and 3P0→3F2transitions, respectively. Furthermore, color coordinates of Pr3+ doped beta-eucryptite nanophosphors are well located in orange-red region. In the dispersion of ac conductivity over the frequency band comprises with two significant frequency nonresponsive and responsive conductive bands. The luminescent unclonable security ink is prepared using Pr3+doped beta-eucryptite nanophosphorsto encode security labels and are completely invisible under normal white light, while it exhibits clear orange-red emission upon ultraviolet 365 nm light. The overall aforementioned results clearly validated that the Pr3+doped beta-eucryptitenanophosphors is establish to be a suitable component for multifunctional applications.