Tunable white light emission from Dy3+/Eu3+ doped LaAlO3 nanophosphors via hydrothermal method

Abstract

A sequence of Dy3+/Eu3+ co-doped LaAlO3 nanophosphors are synthesized by hydrothermal technique and their phase purity, particle nature and luminescence characteristics are investigated. All the prepared samples possess single-phased perovskite type rhombohedral structure of LaAlO3 and consist of polygonal natured particles with the mean size of 30 nm. Under the excitation with 351 nm, LaAlO3: Dy3+ nanophosphors shown characteristic emission peaks of Dy3+ ion and are positioned at 485, 576 and 665 nm. LaAlO3: 9 mol% Dy3+, y mol% Eu3+ nanophosphors exhibited emission bands of both Dy3+ and Eu3+ ions and are noticed at 485, 576, 590, 620 and 696 nm under 351 nm excitation. It can be perceived that the Dy3+ integrated luminescence intensity is reduced and the average lifetime of Dy3+ is decreased with the enhancing Eu3+ content, which is owing to energy migrates from Dy3+ ion to Eu3+ ion. Moreover, CIE coordinate values of LaAlO3: 9 mol% Dy3+, y mol% Eu3+ nanophosphors are altered from the bluish-white to white light and ultimately to the orange-white light location with increasing the Eu3+ ion content. This nature of color adjustable nanophosphors shows the excellent potential advantages in the fields of white light luminescent materials, optoelectronic devices and color displays.