Premium
Preparation of Aluminum Oxynitride by Nitridation of a Precursor Derived from Aluminum–Glycine Gel and the Effects of the Presence of Europium
Author(s) -
Kikkawa Shinichi,
Hatta Naoya,
Takeda Takashi
Publication year - 2008
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2007.02213.x
Subject(s) - europium , spinel , doping , inorganic chemistry , impurity , citric acid , crystallization , materials science , chemistry , luminescence , optoelectronics , organic chemistry , metallurgy
Spinel‐type AlON, Al 2.75 □ 0.25 O 3.74 N 0.26 , was obtained by ammonia nitridation of an oxide precursor prepared by peptizing a glycine gel with aluminum nitrate. To achieve crystallization, the nitrided product had to be annealed at 1500°C for 10 min in flowing nitrogen. The use of glycine instead of citric acid was important for obtaining a white product without residual carbon. A similar preparation method was used for adding small amounts of europium below 10 mol%. A strong blue emission was observed for products ranging from 0.5 to 3.0 mol% Eu doping. The product with 0.5 mol% doping had a maximum emission intensity at 400 nm for an excitation of 254 nm. The products with 1 and 3 mol% doping showed double maxima at 475 and 520 nm. These three emissions were due to the presence of divalent europium in the EuAl 12 O 19 magnetoplumbite‐like aluminum oxynitride impurity mixed with the AlON spinel major phase. The 1 mol% Eu‐doped product exhibited expanded hexagonal lattice parameters ( a =0.5591 and c =2.236 nm) compared with the values for EuAl 12 O 19 magnetoplumbite itself, observed in the 7.7 mol%‐doped product without any strong emission. The above spectrum change was discussed in relation to the coordination around Eu 2+ .