Co掺杂氧化锌的电学和磁学性质的研究

发布时间：2018-05-27 13:27

本文选题：退火 + ZnO　；参考：《人工晶体学报》2017年03期

【摘要】：采用水热合成法实现了Co掺杂氧化锌材料,并对所制备的材料以及在空气中退火材料的电学和磁学性质进行了研究。通过X射线衍射(XRD)、扫描电镜(SEM)等方法对制得样品的结构、形貌进行了表征,结果表明:Zn_(0.9)Co_(0.1)O为六方纤锌矿结构,钴元素的掺入并不改变氧化锌的物相结构。由于掺杂过程中钴元素替代晶格中锌离子的位置,晶格常数发生了改变,同时也影响了材料的性质;退火后样品的晶粒尺寸减小,结晶性变得更好。通过霍尔效应测试系统对样品的电输运性质和磁阻效应进行了分析,结果表明初始样品零场电阻大于退火后样品。磁场对样品内的载流子浓度和迁移率产生了影响,从而影响样品的电导率。两组样品均表现为正磁阻效应,这主要是由于电子局域化作用和能带劈裂效应共同作用的结果,初始样品受到内部晶格缺陷影响,磁阻效应没有持续增加,而经退火处理后的样品内部晶格缺陷减少,水分子导电作用减弱,致使正磁阻作用越来越明显。
[Abstract]:Co-doped zinc oxide materials were fabricated by hydrothermal synthesis. The electrical and magnetic properties of the prepared materials and annealed materials in air were studied. The structure and morphology of the samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the structure of the samples is hexagonal wurtzite, and the doping of cobalt does not change the phase structure of ZnO. Due to the substitution of cobalt for zinc ions in the lattice during doping, the lattice constants change and the properties of the materials are also affected. After annealing, the grain size of the samples decreases and the crystallinity becomes better. The electrical transport properties and magnetoresistive effect of the samples were analyzed by Hall effect test system. The results show that the zero field resistance of the initial sample is greater than that of the annealed sample. The magnetic field has an effect on the carrier concentration and mobility in the sample, thus affecting the conductivity of the sample. Both groups showed positive magnetoresistive effect, which was mainly due to the interaction of electron localization and band splitting effect. The initial sample was affected by internal lattice defects, but the magnetoresistive effect did not increase continuously. However, after annealing, the lattice defects in the samples are reduced, and the conductivity of water molecules is weakened, which results in more and more obvious positive magnetoresistive effect.
【作者单位】：渤海大学新能源学院;
【基金】：国家自然科学基金(11404032,11404034) 辽宁省教育厅一般项目(LY2016002)
【分类号】：TQ132.41

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