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This content will become publicly available on September 21, 2018

Title: Understanding the links between composition, polyhedral distortion, and luminescence properties in green-emitting β-Si 6–zAl zO zN 8–z:Eu 2+ phosphors

Inorganic phosphor materials play a crucial role in the creation of white light from blue and near-UV solid-state light-emitting diodes. Understanding the intricacies of the phosphor structure is key for setting the stage for improved, more efficient functionality. Average structure and coordination environment analysis of the robust and efficient green-emitting phosphor, β-SiAlON:Eu 2+ (β-Si 6–zAl zO zN 8–zEu 0.009), is combined here with a range of property measurements to elucidate the role of Al content ( z) in luminescence properties, including the red shift of emission and the thermal quenching of luminescence as a function of increasing Al content z. Average structure techniques reveal changes in polyhedral distortion with increasing z for the 9-coordinate Eu site in β-SiAlON:Eu 2+. X-ray absorption near edge structure (XANES) is used to confirm that the majority of the activator Eu is in the Eu 2+ state, exhibiting the symmetry-allowed and efficient 4f 75d 0 → 4f 65d 1 transitions. As a result, room temperature and temperature-dependent luminescence indicate a curious increase in thermal stability with increasing z over a small range due to an increasing barrier for thermal ionization, which is correlated to an increase in the quantum yield of the phosphor.
Authors:
ORCiD logo [1] ; ORCiD logo [2] ; ORCiD logo [1] ;  [1] ;  [1] ;  [3] ; ORCiD logo [1]
  1. Univ. of California, Santa Barbara, CA (United States)
  2. Bates College, Lewiston, ME (United States)
  3. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Grant/Contract Number:
AC02-06CH11357
Type:
Accepted Manuscript
Journal Name:
Journal of Materials Chemistry. C
Additional Journal Information:
Journal Volume: 5; Journal Issue: 38; Journal ID: ISSN 2050-7526
Publisher:
Royal Society of Chemistry
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org:
National Science Foundation (NSF); USDOE Office of Science (SC)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
OSTI Identifier:
1399266