溶胶-凝胶法制备La,Y-Mo超微粉末  

Preparation of La,Y-Mo Powder by the Sol-Gel Method

作　　者：刘伟[1] 周美玲[1] 王金淑[1] 陈以欣[1] 郑大威[1] 

机构地区：[1]北京工业大学新型功能材料教育部重点实验室,北京100022

出　　处：《稀有金属材料与工程》2005年第2期291-294,共4页Rare Metal Materials and Engineering

基　　金：国家重点基础研究发展规划基金资助(G19980613132);霍英东青年教师基金资助(81040)

摘　　要：用溶胶-凝胶(Sol-Gel)法制备了 RE(RE=La,Y)-Mo 复合氧化物粉末,工艺条件:初始溶液 pH 值=1,于 550℃分解胶体,500℃,900℃ 2 次还原粉末。采用 XRD,TEM 对还原后粉末的相组成、形貌、粒度进行分析。结果表明:500℃还原后,单质 Mo 衍射峰出现,RE 以非晶态 RE-O-Mo 存在;900℃ 2 次还原后,RE 以氧化物形式存在。红外光谱(FT-IR)分析结果表明,La 和 Y 通过 O 与 Mo 键合,削弱 Mo=O 键,使稀土钼复合氧化物可还原性增强。TEM 分析表明,还原后稀土钼粉末粒径在 70 nm 左右。The La, Y-Mo composite oxide powder was successfully prepared by the Sol-Gel method. The technique terms are as follows: the pH value of the precursor solution is 1; the decomposition temperature is 550 degreesC. The reduction temperature of the first step is 500degreesC and of the second 900degreesC. The composition, microgram and granularity of the powder are studied by the XRD,SEM, etc. The results show that the molybdenum appear after the reduction at 500degreesC and the rare earth elements consist in the structure of RE-O-Mo. After the second reduction, the rare earth elements consist with the form of the rare earth oxide. The results from the infrared spectrum (FT-IR) show that the bond of the Mo = O is weakened due to the bond of the RE-O-Mo, leading to the increase of the reduction properties of the RE-Mo composite oxide powders. The results also show that the granularity of the RE-Mo powder is about 70 nm.

关 键 词：稀土氧化物 钼 溶胶-凝胶 次级发射阴极 

分 类 号：TB383[一般工业技术—材料科学与工程]