白光LED用新型高效红色荧光粉的制备及其发光性能研究

用Na＋做电荷补偿剂,Sm3＋做敏化剂,采用高温固相法制备了Ca0.5MoO4：Eu3＋0.25-x,Sm3＋x,Na＋0.25（x=0,0.001,0.003,0.005,0.008,0.01,0.02,0.03,0.05,0.07,0.09）系列红色荧光粉,实验结果表明：Sm3＋的加入没有改变CaMoO4：Eu3＋,Na＋的晶体结构,也没有改变粉体发射光谱的形状和发射峰的位置,而是加宽了荧光粉CaMoO4：Eu3＋,Na＋激发光谱在400 nm左右的吸收峰,有利于样品的激发峰和近紫外LED芯片相匹配,并且提高了荧光粉在615 nm处发射光谱的发光强度.本文主要对Sm3＋提高荧光粉的发光强度的原理进行探讨,研究结果证明在CaMoO4基质中存在Sm3＋-Eu3＋之间能量传递,此外得出Sm3＋的最佳掺杂浓度是0.5 at.%.

Synthesis and photoluminescence property of novel high-efficiency red emitting phosphors for white light emitting diode applications

Through the use of Sm3＋ as a co-activator and Na＋ as a charge compensation,red emitting phosphors Ca0.5MoO4： Eu3＋0.25？x,Sm3＋x,Na＋0.25（x = 0,0.001,0.003,0.005,0.008,0.01,0.02,0.03,0.05,0.07,0.09） were synthesized by a conventional solid state method.The results showed that the introduction of Sm3＋ did not change the crystal structure and the shape and position of emitting spectra,but extended the excitation region at 400 nm and enhanced the emitting intensity of phosphor at 615 nm.In this work,the principle of Sm3＋ improving the intensity of emitting phosphor was investigated,the energy transfer from Sm3＋ to Eu3＋ in the CaMoO4 host lattice was proved and the optimal doping concentration of Sm3＋ was concluded to be 0.5 at.%.