Tunable long lasting phosphorescence due to the selective energy transfer from defects to luminescent centres via tunnelling in Mn(2+) and Tm(3+) co-doped zinc pyrophosphate.
A series of new phosphors Zn2(0.97-x)P2O7:0.06Tm(3+),2xMn(2+) (0 ≤ x ≤ 0.05) were synthesized and their luminescence properties were investigated. The results showed that the defects in all the phosphors were related to Tm(3+), and Mn(2+) merely served as the emission centres. Tm(3+) also acted as an emission centre and yielded blue phosphorescence corresponding to its characteristic f-f emissions in the phosphors where the Mn(2+) concentration was low (x ≤ 0.001), while in the phosphors with high concentrations of Mn(2+) it mainly served as a defect by forming Tm. The electrons thermally released from defects selectively transferred to Mn(2+) centres mainly through thermally-assisted tunnelling and this resulted in their red to near-infrared phosphorescence. By adjusting the ratio of Mn(2+) to Tm(3+) to control the spectral distribution, tunable long lasting phosphorescence from blue to near-infrared was achieved.
State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China. cyli@ciac.ac.cn.
Ran
R
Pang
Yonglei
Y
Jia
Ran
R
Zhao
Haifeng
H
Li
Jipeng
J
Fu
Wenzhi
W
Sun
Lihong
L
Jiang
Su
S
Zhang
Chengyu
C
Li
Qiang
Q
Su
D011756:Diphosphates / Q000737:chemistry*; D004735:Energy Transfer; D049408:Luminescent Agents / Q000737:chemistry*; D008163:Luminescent Measurements; D008345:Manganese / Q000737:chemistry*; D019265:Spectroscopy, Near-Infrared; D013932:Thulium / Q000737:chemistry*; D017967:Zinc Compounds / Q000737:chemistry*
D011756:Diphosphates; D049408:Luminescent Agents; D017967:Zinc Compounds; D008345:Manganese; D013932:Thulium