论文部分内容阅读
天然方柱石是一种典型的硅酸盐类的发光矿石,针对天然高发光效率方柱石的生成条件及化学成份,采用高温固相法在1100℃弱还原气氛下合成了Na4 Ca4 Al6 Si9 O24(方柱石),并合成了一系列掺杂Ce3+, T b3+的荧光粉,对其晶体结构做了讨论。通过分别对单掺Ce3+,T b3+和共掺Ce3+,T b3+样品发光性质的研究,发现共掺杂的样品其在545 nm处由于T b3+的5 D4→7 F5跃迁发光强度远远大于单掺T b3+的样品。最后通过掺杂不同浓度C e3+样品发光性质的研究,以及其荧光寿命和能量传递机理分析,结果表明随着C e3+掺杂浓度的变化,样品的T b3+的5 D4→7 F5跃迁(545 nm )发光强度及寿命也随着变化,并发现Ce3+对T b3+存在能量传递,且当Ce3+和T b3+的质比为0.02∶0.03时能量传递效率最高。通过色坐标的测量,发现随着Ce3+浓度的改变,样品的发光可在绿色区域进行调节。因此,认为Na4Ca4Al6Si9O24∶Ce3+,Tb3+荧光粉有望成为新型白光L ED荧光粉。“,”Natural scapolite including the S2- impurity is a typical silicate luminescent mineral .According to the formation conditions and chemical composition of natural scapolite ,we synthesized Na4 Ca4 Al6 Si9 O24 (scapo‐lite) by the high temperature solid‐phase reaction ,and prepared the synthetic scapolite phosphors activated with Ce3+ and Tb3+ .The photoluminescence (PL) properties of the obtained phosphors were studied .The re‐sults indicated that the PL intensity of green (545 nm ) emission corresponding to the 5 D4 → 7 F5 transition within Tb3+ in the Ce3+ ,Tb3+‐codoped samples was much higher than that of the Tb3+‐doped samples .The PL properties of the samples activated with various Ce3+ concentrations were measured ,and their fluorescence lifetime and energy transfer mechanism were analyzed .We proved that there was energy transfer from Ce3+ to Tb3+ ,and the energy transfer efficiency was at its maximum when the Ce3+ to Tb3+ mass ratio was 0.02∶0.03 .Upon measurement by chromaticity coordinates ,we found that the luminescence of the samples could be adjusted in the green area with varying Ce3+ concentrations . We thus deem that scapolite phosphors Na4Ca4Al6Si9O24 ∶Ce3+ ,Tb3+ are promising to become the new white LED phosphors .