The reduction of Eu³⁺to Eu²⁺in a new orange-red emission Sr<inf>3</inf>P<inf>4</inf>O<inf>13</inf>: Eu phosphor prepared in air and its photoluminescence properties

Key Words:Strontium compounds;Citrus fruits - Europium - High temperature applications - Luminescence - Optical materials - Phosphors - Photoluminescence - Solid state reactions - X ray powder diffraction;Charge compensation - High temperature solid-state reaction - Orange-red - Orange-red phosphor - Photoluminescence properties - Photoluminescence spectrum - Triclinic systems - WLEDs

Abstract:A new orange-red phosphor Sr<inf>3</inf>P<inf>4</inf>O<inf>13</inf>: Eu was synthesized by a high temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirms the formation of Sr<inf>3</inf>P<inf>4</inf>O<inf>13</inf>in a triclinic system with space group P1&macr;. The photoluminescence spectra indicate that Sr<inf>3</inf>P<inf>4</inf>O<inf>13</inf>: Eu can be excited effectively by near ultraviolet (NUV) light and exhibit bright orange-red emission with excellent color stability. Interestingly, the emission bands of Eu²⁺and Eu³⁺were both observed in the photoluminescence spectra of air-sintered Sr<inf>3</inf>P<inf>4</inf>O<inf>13</inf>: Eu phosphor due to the self-reduction effect. This kind of abnormal reduction was explained by a charge compensation model. &copy; 2014 Elsevier Ltd and Techna Group S.r.l.<br/>

Volume:40

Issue:6

Translation or Not:no