Low Temperature Fabrication fo High Quality Powders by Ultra - fine Grinding under Electrical Discharge

放电超细研磨低温制备高品质粉末

基本信息

批准号：
15360403
负责人：
NAITO Makio
金额：
$ 6.46万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

项目摘要

Composite particles are just key materials which create various kinds of new materials. This study aimed at developing novel powder processing technique to fabricate high quality composite particles rapidly under low temperature processing by making use of ultra-fine grinding mechanism assisted by electrical discharge. The formation mechanism of these powders was also discussed. The experiments started from the development of particle processing apparatus. Then, direct synthesis of composite oxide nanoparticles were conducted without any heat assistance, and the surface modifications of titanium dioxide nanoparticles were also conducted in NH3/N2 gas conditions with glow discharge. For the former experiment, La and Mn powders used in industries were selected, and both powders were processed by the apparatus with high mechanical energy. Consequently, nanosized particles of LaMnO_3 were synthesized only by mechanical energy input without any heat assistance. The reaction route was discussed by a mechanochemical reaction with the assistance of water in the atmosphere. For the latter experiment, nitrogen doping onto the surface of titanium oxide nanoparticles was conducted in the mixed gas of ammonium and nitrogen with glow discharge under mechanical processing. As a result, the nitrogen doping was successfully achieved without any grain growth of nanoparticles. The photocatalytic activity was also obtained by such surface modification under visible light. The doping mechanism was also discussed by a reaction model of nitrogen and titanium dioxides under plasma atmosphere. These results suggest that the processing technique developed by this study is promising for creating various kinds of high functional powders.

复合颗粒是创造各种新材料的关键材料。本研究旨在开发新型粉末加工技术，利用放电辅助的超细研磨机制，在低温加工下快速制造高质量复合颗粒。还讨论了这些粉末的形成机制。实验从粒子处理装置的开发开始。然后，在没有任何热辅助的情况下直接合成复合氧化物纳米颗粒，并在NH3/N2气体条件下辉光放电对二氧化钛纳米颗粒进行表面修饰。前一个实验选择了工业上使用的La和Mn粉末，两种粉末均采用高机械能设备进行加工。因此，LaMnO_3纳米颗粒仅通过机械能输入合成，无需任何热辅助。通过在大气中的水的辅助下进行机械化学反应来讨论反应路线。对于后一个实验，在机械加工下，在氨氮混合气体中，通过辉光放电，在二氧化钛纳米颗粒表面进行氮掺杂。结果，成功地实现了氮掺杂，而没有任何纳米颗粒的晶粒生长。通过可见光下的这种表面修饰也获得了光催化活性。还通过等离子体气氛下氮气和二氧化钛的反应模型讨论了掺杂机理。这些结果表明，本研究开发的加工技术有望用于制造各种高功能粉末。