共沉淀-焙烧法制备球形铝酸锶粉体

以碳酸氢铵、硫酸铝铵和硝酸锶为原料，采用共沉淀法制备了化学组成为SrCO3•2Al(OH)3•7H2O的前体，此前体在较低温度下可合成SrAl2O4粉体。利用红外光谱（FTIR）、扫描电镜（SEM）及能量散射分光光谱（EDS）、X射线衍射（XRD）和热分析（TG-DSC）表征了前体及其热处理产物的特征。结果表明，锶铝物质的量比和pH值对粉体成分和颗粒形貌有显著影响，n(Sr)∶n(Al)=1∶1.6、pH=7.6条件下制备了球形前体，此前体在1 100 ℃于空气气氛中焙烧2 h获得了单分散、球形SrAl2O4粉体，合成温度较传统高温固相法低约400 ℃。

Preparation of spherical SrAl2O4 powders by coprecipitation-calcination process

SrAl2O4 is one of the most important martrix materials for the long persistence phosphors. The precursors with composition of SrCO3•2Al(OH)3•7H2O were prepared by the co-precipitation method from NH4HCO3，NH4Al(SO4)2•12H2O and Sr(NO3)2，and SrAl2O4 powders were obtained from sintering the precursors at a lower temperature than the traditional solid state method. The precursors and the products were characterised with FTIR，SEM，EDS，XRD and TG-DSC. The results indicated that the compositions and surface shapes of samples were greatly affected by molar ratios of Sr and Al and pH. The spherical precursors were prepared with terms of n(Sr)∶n(Al)= 1∶1.6 and pH=7.6，and the mono-dispersed and spherical SrAl2O4 powders were synthesized from sintering the precursors at 1100℃ for 2 h in the air，which was about 400℃ lower than the traditional high temperature solid state method.