A novel approach on the synthesis of beta-SiAlON:Eu2+ phosphors from kaolin through carbothermal reduction and nitridation (CRN) route


Yurdakul H., Ceylantekin R., Turan S.

ADVANCES IN APPLIED CERAMICS, vol.113, no.4, pp.214-222, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 113 Issue: 4
  • Publication Date: 2014
  • Doi Number: 10.1179/1743676114y.0000000141
  • Journal Name: ADVANCES IN APPLIED CERAMICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.214-222
  • Keywords: Ceramic, Electron microscopy, Nitrides, SiAlON, Luminescence, Carbothermal reduction and nitridation, BETA-SIALON POWDER, LUMINESCENCE PROPERTIES, CRYSTAL-STRUCTURE, OXYNITRIDE, CERAMICS, PHOTOLUMINESCENCE
  • Anadolu University Affiliated: Yes

Abstract

Doping beta-SiAlON crystal structure with rare earths leads to a superior tuneable luminescence properties for light emitting diodes (LEDs). However, the widely used conventional methods require high purity starting powders and time consuming processes. Here, a new approach to synthesise Eu2+ activated beta-SiAlON phosphors from kaolin through carbothermal reduction and nitridation route was introduced. The Rietveld refinement on powder X-ray diffraction method and scanning electron microscopy with energy dispersive X-ray spectroscopy analyses showed that 78 center dot 28 wt% Eu2+ doped beta-Si6-zAlzOzN8-z (z=2 center dot 1) was successfully obtained. Photoluminescence examinations under the 267 nm excitation revealed two distinct broad emission peaks: maxima at around 415 nm (violet) and 540 nm(green). Transmission electron microscopy observations demonstrated the incorporation of Eu2+ ions into beta-SiAlON grains giving the observed violet and green emissions. It is anticipated that this study paves a way for cost effective synthesis of rare earth doped single phase beta-SiAlON phosphors in LED applications.