以CaCO3(99.9%)、Li2CO3(99.9%)、Na2CO3(99.9%)K2CO3(99.9%)、H3BO3(99.9%)、Sm2O3(99.9%)为原料,按所设计的化学计量比称取以上原料,在玛瑙研钵中混合均匀并充分研磨,装入刚玉坩埚,采用固相法制备LiCaBO3:Sm^3+材料;通过美国XRD6000型X射线衍射仪和日本岛津RF-S40荧光分光光度计对材料的性能进行表征,所有测量均在室温条件下进行。LiCaBO3:Sm^3+材料的发射光谱由三个橙红色发射峰组成,主峰位于561,602,651nm,分别对应Sm^3+的^4G5/2→6H5/2,^4G5/2→H7/2和^4G5/2→H9/2跃迁;监测602nm发射峰,得到其激发光谱由320—420nm的宽激发带组成。由激发和发射光谱看出,LiCaBO3:Sm^3+能够有效地被紫外LED芯片激发,发射红色光。研究了Sm^3+浓度(x)对LiCa1-xBO3:xSm^3+材料发射强度的影响,结果表明:随Sm^3+浓度的增大,发射强度先增强后减弱,Sm^3+掺杂摩尔分数为3%时,发射强度最大,依据Dexter理论,计算得出其浓度猝灭机理为电偶极-偶极相互作用。掺入电荷补偿剂Li^+、Na^+和K^+均提高了LiCaBO3:Sm^3+材料的发射强度。
LiCaBO3: Sm3+ phosphor was synthesized by solid state reaction and its luminescent properties were studied. The emission spectrum consists of three major orange-red emission bands at 561, 602 and 651nm, which correspond to the 4 G5/2→6 H5/2, 4 G5/2→6 H7/2 and 4 G5/2→6 H9/2 typical transitions of Sm3 +, respectively. The excitation spectrum for the strongest emission (602 nm) extends in 320 ~ 420 nm, which indicated that this phosphor can be effectively excited by near-ultraviolet light-emitting diodes. The influences of Sm3 + concentration (x) on the emission intensity of LiCaj- BO3:xSm3~ phosphors were also investigated. The results showed that the intensity increases with increasing Sm3+ concentration, then decreases, and reaches the maximal value at 3% Sm3+. And the concentra- tion self-quenching mechanism is the d-d interaction according to Dexter theory. The emission intensity of LiCaBO3: Sm3+ can be. enhanced by doping charge compensator Li +, Na+, K +.