CaS:Sm^(3+)中Sm^(3+)的发光特性与其格位对称性的相关性

利用固相反应法合成了不同浓度Ｓｍ ３＋ 掺杂的ＣａＳ荧光粉．研究了Ｓｍ ３＋ 在ＣａＳ基质中的发光特性与其格位对称性的相关性．发现Ｓｍ ３＋ 掺杂浓度较低时，其电荷补偿方式所引起的晶格畸变程度较小，Ｓｍ ３＋ 仍处于对称性格位．当Ｓｍ ３＋ 的掺杂浓度增加，其主要的电荷补偿方式所引起的晶格畸变程度较大，且占据非对称性格位的Ｓｍ ３＋ 浓度相对增加．

Photochromism in CaS:Sm

The photochromism in CaS:Sm (from white to pink) was observed for the first time by exposing it to ultraviolet light. The experiments results show that the absorption intensity of Sm2+ in the range of 500 similar to 600nm was strongly increased after irradiation. This reveals that there is the valence changing of Sm. If the sample was excited by visible light again, the pink color turned to white, indicating that CaS:Sm has potential application in the field of storage material.

Li_2Ca_(1-x)Sr_xSiO_4∶Sm^(3+)的制备及发光性能

高温固相法合成Li2Ca1-xSrxSiO4∶Sm3+发光材料。通过XRD、SEM和PL表征物质结构、形貌和发光性能。研究表明,在近紫外光激发下,Li2CaSiO4∶Sm3+、Li2SrSiO4∶Sm3+和Li2Ca1-xSrxSiO4∶Sm3+(x=0.3~0.6)分别发出位于(563nm、607nm、649nm)、(559nm、599nm、645nm)和(563nm、599nm、645nm)的发射峰,其CIE位于红橙光区域。Sr2+部分取代Ca2+后,Li2Ca1-xSrxSiO4∶Sm3+(x=0.3~0.6)发射峰的位置不变,Sm3+发光强度降低,其中Li2Ca0.5Sr0.5SiO4∶Sm3+相对较高。加入4.5%Na2CO3电荷补偿剂后,Li2Ca0.5Sr0.5SiO4∶Sm3+发光强度提高了2.8倍,表明Li2Ca0.5Sr0.5SiO4∶Sm3+可作为LED用发光材料。