Near-white photoluminescence in paramagnetic Gd6O5F8 nanoparticles

Abstract

White light emission has been achieved by near full band excitation from 10.7 nm sized pure Gd₆O₅F₈ nanoparticles. The position of the photoluminescence (PL) spectrum and the peak of the excitation spectrum show an obvious shift toward the red region, which increases with the excitation wavelength and the monitoring wavelength, respectively. Four kinds of emission state could exist on the surface of the Gd₆O₅F₈ nanoparticles in cyclohexane. Multiple emission states with excitation-dependent PL are generated in Gd₆O₅F₈ nanoparticles in cyclohexane, which are attributed to the inhomogeneous properties. Besides, Gd₆O₅F₈ nanoparticles in cyclohexane exhibit high thermal stability and good paramagnetic properties. When the heating temperature reached 85 °C, the relative intensity was decreased to 69%. This work provides a new understanding of complex luminescence and a novel reference for a biological, white light-emitting diode (WLED) and other multi-functional applications.