PH值对YBCO纳米粉末制备工艺及性能的影响

采用溶胶-凝胶法制备YBa2Cu3O7纳米粉末,用XRD和SEM对粉体进行表征,结果发现PH值对颗粒大小、粉体纯度影响很大。当溶液PH值为6.5,烧结温度为800℃,烧结时间为5h时,制得的YBCO纯度高、颗粒小。原因在于当PH值为6.5时,柠檬酸能与溶液中的所有金属离子形成稳定的柠檬酸盐,且各金属离子形成的化合物溶解度高,不易随溶剂的蒸发而析出,避免了样品中成份的偏离。最终制得的粉体纯度高、颗粒分散性好,颗粒尺寸小于30nm。

The influence of PH value on YBCO nanopowder preparation craft and performance

YBCO nanopowders is prepared by sol-gel method,and the nanoscale powders is examined by X-ray diffraction and scanning electron microscopy.It is found that particle size and purity powders obtained by the PH value of impact.When the PH value of 6.5 and the colloform is sintered at 800℃ for 5 hours,we can obtain the sample have small grain size and high purity.The reason is that citric acid solution with all the metal ion form a stable salt of citric acid,when the PH value of 6.5.In this condition,the metal ions to form compounds of high solubility.It is not easy with the solvent evaporation and precipitation to avoid deviation from the sample components,system may affect the quality of YBCO colloidal.Eventually obtained a high purity powder,particle dispersion,and the particle size less than 30nm.