Enhanced emission of CaNb$_2$O$_6$ : Sm$^{3+}$ phosphor by codoping Na$^+$/B$^{3+}$ and the emission properties

[摘要] Renping Cao1 Zhengdong Qin1Shenhua Jiang2Aihui Liang3Zhiyang Luo4Xiaoguang Yu1

[学科分类] 材料工程

[关键词] A series of CaNb$_2$O$_6$:$x$Sm$^{3+}$ ($0 \le x \le 10$ mol%) and CaNb$_2$O$_6$:Sm$^{3+}$, Na$^+$/B$^{3+}$ phosphors were synthesized by the solid-state reaction method in air. Their crystal structures and luminescence properties were investigated and analysed, respectively. Host CaNb$_2$O$_6$ emitted blue light with excitation 270 nm. CaNb$_2$O$_6$:$x$Sm$^{3+}$ phosphors showed a systematically varied hue from blue to white by changing Sm3+ ion concentration from 0 to 10 mol% with excitation of 270 nm and their chromaticity coordinates were the regions from (0.1665, 0.1767) to (0.2484, 0.2260). Luminescence properties of CaNb$_2$O$_6$:$x$Sm$^{3+}$ phosphor were tuned and improved significantly by codoping B$^{3+}$ or Na$^+$ ions. Energy transfer between Nb$_2$O$^{2-}_6$ group and Sm$^{3+}$ ion was observed and analysed via luminescence properties. The luminous mechanism was explained by energy level scheme and energy transfer process in CaNb$_2$O$_6$:$x$Sm$^{3+}$ phosphor. The strong excitation band peaking at ∼407 nm indicated that the CaNb$_2$O$_6$:$x$Sm$^{3+}$, Na$^+$/B$^{3+}$ phosphor has a potential application in white light-emitting diodes based on near-UV LED chip.