溶胶-凝胶自燃烧法制备Y_(2)BaCuO_(5)粉体:XRD图谱分析pH影响  

SOL-GEL AUTO-COMBUSTION SYNTHESIS Y_(2)BaCuO_(5) POWDER:XRD PATTERNS INVESTIGATE THE pH INFLUENCE

作　　者：孙丽娜[1,2] 孙爱民[1,2] 周敏[1,2] 韩佩佩[1,2] 张永福[1,2] 王洁琼[1] 

机构地区：[1]西北师范大学物理与电子工程学院,兰州730070 [2]甘肃省原子分子物理与功能材料重点实验室,兰州730070

出　　处：《低温物理学报》2013年第2期102-108,共7页Low Temperature Physical Letters

基　　金：甘肃省高等学校基本科研业务费项目(2010年~2012年)资助的课题.

摘　　要：采用溶胶-凝胶自燃烧法制得了柠檬酸盐络合物,该络合物经960℃煅烧7小时得到了纳米尺寸的Y2BaCuO5(Y211)细粉。利用XRD对不同pH下的纳米尺寸Y211粉体特性如物相鉴定,晶粒尺寸,晶格常数等进行测量。实验发现干凝胶在空气中点燃后存在自蔓延燃烧。初始溶液中pH值影响了干凝胶自燃烧的过程,决定了自燃烧和煅烧粉体的晶格常数,密度,体积以及粒子尺寸。当pH=7,煅烧粉体的XRD图谱表明煅烧后粉体的平均晶粒尺寸(25nm)远小于自燃烧粉体的平均晶粒尺寸(48nm)。此外,pH=5的煅烧粉体的晶格常数有一个最小值,而密度则达到了最大值6.224g/cm3。Y2 BaCuO5 （Y211） powders with nanocrystalline sizes were produced by nitrate-citrate gel auto-combus- tion method after as-burnt powder be sintered at 960℃ for 7 hours. The synthesized nano-sized Y211 powders at different pH were characterized with respect to phase identification, crystallite size and lattice parameter determina- tion using X-ray diffraction. Experiments revealed that dried gel which derived from citrate and nitrate sol exhibits self-propagating combustion when it was ignited in air. The pH in the starting solution affected the combustion process, and then determined the lattice parameters, the density, the unit-cell volume and the particle size of the as- synthesized and calcined powder, when pH = 7 , XRD patterns of the calcined powders showed that the smaller av- erage crystallite sizes powder（25nm） was produced than as-burnt powders（48nm）. In addition, the data from XRD showed the lattice parameters a , b and c of calcined powders, had a minimal value and the density went up to 6. 224 g/cm3 with pH=5.

关 键 词：PH 溶胶-凝胶 纳米粒子 Y211 

分 类 号：TB383.1[一般工业技术—材料科学与工程] O614.322[理学—无机化学]