( 北京工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院，
新型功能材料教育部重點(diǎn)實(shí)驗(yàn)室， 北京 100022)
摘 要: 采用溶膠-凝膠(Sol-Gel)法成功制備了(La, Y)2O3-Mo超細(xì)粉末，利用XRD、 TEM對(duì)還原后粉末相結(jié)構(gòu)、 形貌、 粒度等進(jìn)行了分析。結(jié)果表明： 900℃二次還原后， 鉬以單質(zhì)形式存在，稀土以氧化物形式存在。 TEM觀察表明，還原后稀土鉬粉末粒徑在70nm左右，粒度分析表明粉末D(n, 50)=80nm。 紅外光譜（FT-IR）分析表明， 鑭和釔通過(guò)氧與鉬鍵合，削弱Mo=O鍵， 使稀土鉬復(fù)合氧化物可還原性增強(qiáng)。能譜分析顯示燒結(jié)體中稀土元素分布均勻。
關(guān)鍵字: 稀土氧化物； 鉬； 溶膠-凝膠； 次級(jí)發(fā)射陰極
Sol-Gel method
CHEN Yi-xin1， LI Na
（ Key Laboratory of Advanced Functional Materials, Ministry of Education，School of Materials Science and Engineering， Beijing University of Technology，Beijing 100022， China）
Abstract: 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℃. The reduction temperature of the first step is 500℃ and that of the second is 900℃. The composition, microgram and granularity of the powder are studied by XRD and SEM experimental methods. The results show that the molybdenum appears after the second reduction at 900℃ and the rare earth oxide is present in the powder. The results of TEM show that the granularity of the RE-Mo powder is about 70nm and the average granularity is 80nm from the results of granularity analysis. The results from the infrared spectrum(FT-IR) show that the bond of Mo=O is weakened due to the bond of RE—O—Mo, which leads to the increase of the reduction properties of the RE-Mo composite oxide powders. The SEM result indicates the uniform distribution of RE elements in the sintering body.
Key words: rare earth oxides; molybdenum; Sol-Gel; second emission cathode
