摘要
采用高温高压方法将由溶胶-凝胶(Sol-gel)法制备的Co掺杂ZnO基稀磁半导体纳米颗粒置于6GPa压强和1000℃环境中处理,并研究其结构和磁学性质.XRD,XPS以及HRTEM等结构测量和分析表明,在掺杂浓度不高时,Co2+离子被较好地掺杂到了ZnO晶格中,没有第二相或者团簇存在;而在中高浓度掺杂时,有CoO相形成.SQUID磁性测量显示,样品具有室温铁磁性.
High-pressure and high-temperature are used to treat a series of Co doped ZnO samples synthesized by Sol-gel method. Structure and composition analyses suggest that CoO is formed after increasing the Co concentration under the high-pressure condition. The results of magnetism measurements by SQUID show that all the samples have room-temperature ferromagnetism and the ferromagnetism increases as the Co doping concentration increases,despite the formation of antiferromagnetic CoO under the high pressure condition. Thus,we argue that the ferromagnetism of ZnCoO is intrinsic.
基金
国家重点基础研究发展规划(批准号:2006CB604907)
国家高技术研究发展计划(批准号:2006AA03A142
2006AA03Z411)
国家自然科学基金(批准号:60731160628
60776001)资助项目~~
