制备条件对氧化镨钕物理性能的影响研究

Effect of Preparation Conditions on The Physical Properties of Pr-Nd Oxides

以氯化镨钕溶液为原料液,碳酸氢铵为沉淀剂,在常温、50℃、90℃三个温区制备氧化镨钕前驱体并焙烧制备了氧化镨钕,运用XRD、SEM、TG-DSC、粒度分析等表征手段,研究了沉淀温度和焙烧温度对镨钕氧化物的粒度、形貌、晶型等物理性能的影响。结果表明,当沉淀温度<90℃,得到含不同结晶水的碳酸镨钕,而当沉淀温度≥90℃,得到碱式碳酸镨钕;氧化镨钕及其前驱体的形貌随沉淀温度的升高均由块状团聚体逐渐变为类球形颗粒;当焙烧温度≥750℃时,才出现明显的氧化镨钕衍射峰且晶型为立方晶型,而焙烧温度升高到950℃时,氧化镨钕的晶型已完全转变为六方晶型。

（ Pr, Nd） mixed oxides were prepared by calcinating （ Pr, Nd） mixed oxides＇ precursor in the range of 150℃ to 950℃ with （ Pr, Nd） mixed cilorides solution as raw material liquid and ammonium bicarbonate as precipitant and precipi- taed at room temperature,50℃ and 90℃ ,respectively. Effect of precipitation temperature and calcination temperature on par- ticle size, morpholoty and crystalline of （Pr, Nd） mixed oxides were investigated with XRD, SEM,TG - DSC, particle size ana- lyzer. The results showed that the praseodymium neodymium carbonates with different crystalline water prepared at the precipi- tation temperature below 90℃ , and when the precipitation temperature was above 90 ℃ , it was obtained to Nd（Pr） OHCO3 ; As the precipitation temperature increases, morphology of massive aggregates of （Pr, Nd） mixed oxides and its precursor grad- ually transformed into spherical particles. When the calcination temperature was above 750℃ , it exhibits （Pr, Nd ） mixed ox- ides diffraction peaks and its crystalline was cubic crystal, but the calcination temperature increased to 950℃, its crystalline has been completed transformed into hexagonal crystal.