共沉淀—超临界流体干燥法制备ZrO_2(Y_2O_3)纳米粉

Preparation of ZrO_2(Y_2O_3) nano-powders by coprecipitation-supercritical fluid drying method

采用共沉淀—超临界流体干燥法制备出ZrO2 (Y2 O3 )纳米粉 .研究了位阻剂、超临界流体干燥处理工艺和晶化温度对粉末性能的影响 .研究结果表明 :用该法制备的粉末可以有效地防止干燥过程中粒子间的团聚 .选择聚乙二醇 (PEG)作为位阻剂 ,采用 2 6 0℃× 7.5MPa的超临界流体干燥处理和 6 5 0℃× 1 .5h的晶化处理制度 ,可以得到颗粒团聚程度小、近球形、平均粒度小于 4 0nm的以四方相为主的ZrO2 (Y2 O3 )

Coprecipition_supercritical fluid drying(SCFD) method is used for synthesis of Y_2O_3_partly_stabilized ZrO_2 nano_powders.The effect of surface active agent,supercritical drying temperature,pressure and holding time,calcination temperature and holding time on the properties of powders are studied.The results show that the resulting ultrafine powders have small particle size,high surface area,better spherical grain.This method improves effectively the aggregation behaviour of nanoparticles during the gel drying process.When supercritical drying process conducts at 260 ℃ and 7.5 MPa for 0.5 h,and then calcinats at 600 ℃ for 1.5 h,the properties of powders are much better,the mean size of ZrO_2(Y_2O_3)particle is about 10 nm.