a-M3B2N4 (M = Ca, Sr):Eu3+: A Nitride-based Red Phosphor with a Sharp Emission Line and Broad Excitation Band Used for WLED

作者：Ding, Jianyan; Wu, Quansheng; Li, Yanyan; Long, Qiang; Wang, Yichao; Ma, Xinlong; Wang, Yuhua

来源：Journal of Physical Chemistry C, 2017, 121(18): 10102-10111.

DOI：10.1021/acs.jpcc.7b01945

• LIGHT-EMITTING-DIODES
• WHITE-LIGHT
• LUMINESCENCE PROPERTIES
• PHOTOLUMINESCENCE
• PARTICLES
• LEDS
• EU3+

For solving the problem that Eu3+ -activated phosphors cannot be well excited by the near UV-LED chips, the charge transfer band (CTB) of Eu3+-N3- in alpha-M3B2N4 (M = Ca, Sr) has been investigated in this work. Compared with the sharp excitation peaks due to the f-f transitions of Eu3+, the charge transfer band is broad and the excitation band of alpha-M3B2N4 (M = Ca, Sr):Eu3+ centered at 370 or 350 nm lies in near-UV, implying a promising excitation. The electron and crystal structures of alpha-M3B2N4 (M = Ca, Sr) has been analyzed in detailed, indicating that they all crystallize in cubic phase with the space group (Im (3) over barm) and have similar band-gap structures. The double bond of [N = B=N](3-) combining with the face-shared (Ca, Sr)N-6 octahedron forms the stable and compact crystal structure, and the band gap with the value about 4 eV is suitable for Eu3+ to form a luminescent center. Under near-UV excitation, the sharp red light that peaked at 613 and 593 run resulting from the f-f transition of Eu3+ ions has been obtained. The optimal concentration of Eu3+ in the alpha-M3B2N4 (M = Ca, Sr) has been measured, and the decay curves of samples prove that the energy transfer happens between Eu3+ ions through the dipole-dipole interaction. The thermal stability of samples has been measured to access their application in the WLED.

• 出版日期2017-5-11
• 单位兰州大学