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Microanalysis of Calcium Codoped LaAl(Si 6− z Al z )(N 10− z O z ) ( z ~1): Ce 3+ Blue Phosphor
Author(s) -
Takahashi Kohsei,
Dierre Benjamin,
Cho Yujin,
Sekiguchi Takashi,
Xie RongJun,
Hirosaki Naoto
Publication year - 2015
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/jace.13470
Subject(s) - cathodoluminescence , phosphor , analytical chemistry (journal) , sialon , microanalysis , materials science , emission spectrum , mineralogy , spectral line , crystallography , ceramic , chemistry , luminescence , metallurgy , physics , optoelectronics , organic chemistry , chromatography , astronomy
Cathodoluminescence spectra of Ca codoped (La,Ce)Al(Si 6− z Al z )(N 10− z O z ) ( z ~1) (termed JEM phase) phosphors were analyzed microscopically. The as‐prepared samples consisted of a major JEM phase and a small amount of β‐sialon and/or α‐sialon depending on the Ca concentration. A microscale distribution of three different emission spectra was clearly observed on one phosphor particle, which was originated from the blue‐emitting JEM:Ce (430 nm), β‐sialon:Ce (435 nm) and Ca‐α‐sialon:Ce (475 nm), respectively. The volume ratio of the three phases thus led to changes in the bandwidth and the maximum position of the emission spectrum, and the redshift of CL spectra with increasing Ca concentration was dominantly attributed to the enhanced emission from Ca‐α‐sialon. The microanalysis of phosphor particles with the aid of cathodoluminescence spectroscopy indicated a similar result of the phase assembly that was identified by the powder X‐ray diffraction.