1) The document describes the development of a new oxynitride-based phosphor called Y10Al2Si3O18N4:Re3+ (YAlSiON:Re3+) that can efficiently convert near-UV light from LEDs into blue, green, and orange colors. 2) By controlling the composition, the phosphor can produce tricolor emission without reabsorption of green and orange light in the blue region. 3) Energy transfer mechanisms allow production of blue light from Ce3+, green light from Ce3+-Tb3+ transfer, and orange light from Ce3+ → Tb3+ → Eu3+ transfer, enabling full-color emission from a

1. The 2nd International Workshop on Persistent and Photostimulable Phosphors
Spectral Tuning of an Oxynitride-based Phosphor: Full-color Emitting
Realization for near-UV LEDs
Yongchao Jia, Wei Lü, Ning Guo, WenZhen Lü, Qi Zhao, and Hongpeng You *
1,2
1
1,2
1,2
1,2
1,
State key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese
Academy of Sciences, Changchun 130022, P. R. China
2
Graduate University of the Chinese Academy of Sciences, Beijing 100049, P. R. China.
1
Introduction
Optical behavior of Ce
With the characteristic merits and promising application,
solid state lighting in the form of white light-emitting
diodes (LEDs) have attracted considerable attention in the
past few years. To generate white light from LEDs, the
most frequent and simple method is to combine an InGaNbased blue diode with the yellow phosphor material
Y3Al5O12:Ce3+. Although the path of white light realization
is inexpensive and efficient, it suffers the disadvantages
such as high correlated color temperature (CCT) and low
color-rendering index (CRI) due to the deficiency of the
red emission. An alternative way to produce white is to
use a near ultraviolet (n-UV) LED chip with red, green,
and blue phosphors. Compared with the above “Blue +
Yellow”, the “n-UV +blue/green/red” would exhibit
superior color hue tuning and low color point variation
against the forward-bias currents. With the development of
the efficient LEDs that emit light in the n-UV range, the
most research interest has been paid to this approach to
attain high color rendering and wide range of color
temperatures. Even though the great promise of this
method, there are also some problems which should be
solved, and can be grouped into two categories: 1. One
challenge is to develop novel down-conversion phosphors
that will harvest the n-UV light from LEDs and convert it
efficiently into the targeted colors that required for high
quality white light. 2. The other challenge that is to avoid
the re-absorption of the green and red phosphors in the
blue region, for enhancement of the luminous efficiency.
Work Brief
In the present paper, we describe the synthesis and
luminescent properties of a new oxynitride-based
phosphor, Y10Al2Si3O18N4:Re3+ (YAlSiON:Re3+, Re = Ce,
Tb, Eu), which can answer the above problems to some
degree. The near-UV convertible tricolor (blue, green, and
orange) phosphors were obtained through properly
controlling the composition of the powder, while the reabsorption of the green/orange phosphor in the blue region
was prevented. Detail information was given in three
aspects: 1. The blue phosphor YAlSiON:Ce3+: the
luminescence behavior of Ce3+ doped YAlSiON sample
were studied in detail, and concentration-dependence
emission spectra were investigated. 2. The green phosphor
YAlSiON:Ce3+,Tb3+: the Ce3+-Tb3+ energy transfer in
YAlSiON powder was justified, the related mechanism as
well as the ability of color point tuning were pointed out.
3. The orange phosphor YAlSiON:Ce3+,Tb3+,Eu3+: the
sensitizing Eu3+ with Ce3+ ion was realized through
utilizing the Tb3+ as an intermediate, and the Ce3+ →
(Tb3+)n → Eu3+ energy transfer scheme were performed,
the optimal concentration of Tb3+ ion was also determined.
Energy transfer Scheme
Ce3+
Energy
Energy
Tb3+
Energy
Eu3+
Energy
3+
Ce -Tb energy transfer
3+
3+
Ce -Tb -Eu energy transfer
3+
3+
3+
Conclusion
In conclusion, a series of novel near-UV convertible phosphors Y 10Al2Si3O18N4:Re3+ (YAlSiON:Re3+,
Re = Ce, Tb, Eu) were synthesized via solid state method. Spectra evaluation for aiming to full coloremitting has been perfectly realized through the energy transfer phenomenon between Re 3+ ions pair.
Detail results show that the electric dipole-dipole interaction dominates the Ce 3+-Tb3+ energy transfer
mechanism, while the process of the sensitizing Eu3+ with Ce3+ and Tb3+ ions follows the Ce3+ →
(Tb3+)n → Eu3+ scheme and a high Tb3+ concentration is indispensable for that. Ideal white can be
expected to obtain from the combination of a near-UV chip with the composition-optimal powder
blends:
YAlSiON:0.05Ce3+
(blue),
YAlSiON:0.05Ce3+,0.25Tb3+
(green)
and
YAlSiON:0.05Ce3+,2.00Tb3+,0.05Eu3+ (orange), which reflects the potential application of the obtained
powders.