CaLa4Si3O13:Eu3+红色荧光粉制备条件优化及助熔剂作用研究

采用高温固相法制备了CaLa4Si3O13:Eu3+红色荧光粉,研究了助熔剂总量、Li和B物质的量之比、烧成温度对发光性能的影响。以Eu3+的5 D0-7 F2发射强度为指标得出的最佳制备条件为:硼锂双助熔剂B和Li物质的量之比为1:1,总量为0.4 mol.mol-1,950℃预烧150 min,1150℃,240 min烧成。硼组分进入晶格置换硅,使晶胞参数a,c和晶胞体积V均逐渐减小,提高电/磁偶极跃迁强度比和总发光强度。助熔剂总量达到0.24 mol.mol-1后,进入基质的硼趋于饱和。硼组分起到助熔剂和基质组分置换双重作用。

Preparation of CaLa4Si3O13:Eu3+ Red Light Emitting Phosphor and Influence of Flux

The phosphor CaLa4Si3O13:Eu3+ was prepared via solid-state reaction.The effects of the total amount of double flux,the molar ratio of Li and B in the flux,and the sintering temperature on the luminescent properties were investigated.The appropriate synthesis conditions were confirmed as that the ratio of Li and B was 1∶ 1 in mole and the amount of double flux was 0.4 mol · mol-1 and pre-sintered at 950 ℃ for 150 min and then sintered at 1150 ℃ for 240 min,and these conditions referred to the best emission intensity of 5D0-7F2 transition of Eu3+ in the host.The boron component in the flux would come into the host lattice and substitute Si,so that the lattice parameters a,c and cell volume V of phosphor were reduced.Therefore,the emission intensity and the area ratio of peeks from electronic/magnetic dipole transitions were increased.The saturation concentration of boron entering host was approached while the total of double flux exceed 0.24 mol · mol-1.The boron component acted a dual role as flux and lattice replacement reagent.