abstract
In this work, a latent energy-transfer process in traditional Eu3+,Tb3+-doped phosphors is proposed and a new class of Eu3+,Tb3+-doped Na4CaSi3O9 (NCSO) phosphors is presented which is enabled by luminescence decay dynamics that optimize the electron-transfer energy process. Relative to other Eu3+,Tb3+-doped phosphors, the as-synthesized Eu3+,Tb3+-doped NCSO phosphors show improved large-scale tunable emission color from green to red upon UV excitation, controlled by the Tb3+/Eu3+ doping ratio. Detailed spectroscopic measurements in the vacuum ultraviolet (VUV)/UV/Vis region were used to determine the Eu3+-O2- charge-transfer energy, 4f-5d transition energies, and the energies of 4f excited multiplets of Eu3+ and Tb3+ with different 4f(N) electronic configurations. The Tb3+-> Eu3+ energy-transfer pathway in the co-doped sample was systematically investigated, by employing luminescence decay dynamics analysis to elucidate the relevant energy-transfer mechanism in combination with the appropriate model simulation. To demonstrate their application potential, a prototype white-light-emitting diode (WLED) device was successfully fabricated by using the yellow luminescence NCSO:0.03Tb(3+), 0.05Eu(3+) phosphor with high thermal stability and a BaMgAl10O17:Eu2+ phosphor in combination with a near-UV chip. These findings open up a new avenue to realize and develop multifunctional high-performance phosphors by manipulating the energy-transfer process for practical applications.
keywords
LUMINESCENCE PROPERTIES; EU3+; PHOSPHORS; TB3+; PHOTOLUMINESCENCE; SPECTROSCOPY; EUROPIUM; CE3+; SM3+
subject category
Chemistry
authors
He, J; Yan, C; Huang, MM; Shi, R; Chen, YB; Ling, CD; Liu, ZQ
our authors
Rui Shi
Researcheracknowledgements
C.Y. and C.D.L. acknowledge the financial support from Australian Research Council (ARC) Discovery Project (Grant No. DP190101862). The authors would like to thank Professor Brendan J. Kennedy from The University of Sydney for reviewing the manuscript and helpful suggestions. This work was supported by the National Natural Science Foundation of China (Grant No. 21875048), the Guangdong Natural Science Foundation (Grant No. 2017A030311016 and 2018A030310339), Major Scientific Project of Guangdong University (Grant No. 2017KZDXM059 and 2018KQNCX196), Yangcheng Scholars Research Project of Guangzhou (Grant No. 201831820), Science and Technology Research Project of Guangzhou (Grant Nos. 201804010047 and 201904010497), Guangzhou University's 2017 Training Program for Young Top-Notch Personnel (BJ201704).