Luminescence enhancement of (Sr1–xMx)2SiO4:Eu2+ phosphors with M (Ca2+/Zn2+) partial substitution for white light‐emitting diodes

Eu²⁺‐doped Sr₂SiO₄ phosphor with Ca²⁺/Zn²⁺ substitution, (Sr_1–xM_x)₂SiO₄:Eu²⁺ (M = Ca, Zn), was prepared using a high‐temperature solid‐state reaction method. The structure and luminescence properties of Ca²⁺/Zn²⁺ partially substituted Sr₂SiO₄:Eu²⁺ phosphors were investigated in detail. With Ca²⁺ or Zn²⁺ added to the silicate host, the crystal phase could be transformed between the α‐form and the β‐form of the Sr₂SiO₄ structure. Under UV excitation at 367 nm, all samples exhibit a broad band emission from 420 to 680 nm due to the 4f⁶5d¹ → 4f⁷ transition of Eu²⁺ ions. The broad emission band consists of two peaks at 482 and 547 nm, which correspond to Eu²⁺ ions occupying the ten‐fold oxygen‐coordinated Sr.(I) site and the nine‐fold oxygen‐coordinated Sr.(II) site, respectively. The luminescence properties, including the intensity and lifetime of Sr₂SiO₄:Eu²⁺ phosphors, improved remarkably on Ca²⁺/Zn²⁺ addition, and promote its application in white light‐emitting diodes. Copyright © 2016 John Wiley & Sons, Ltd.