Electrical Transport Properties of Large, Individual NiCo2O4 Nanoplates
Electrical Transport Properties of Large, Individual NiCo2O4 Nanoplates
复制标题
大型单个 NiCo2O4 纳米板的电传输特性
DOI：
10.1002/adfm.201102155
复制
发表时间：
2012-03-07
影响因子：
19
通讯作者：
Fang, Xiaosheng
中科院分区：
文献类型：
--
作者：
Hu, Linfeng;Wu, Limin;Fang, Xiaosheng
了解单个半导体纳米结构的电输运特性对于推进其在高性能纳米器件中的实际应用至关重要。具有光滑表面的大尺寸单个纳米结构是首选，因为它们可以很容易地使用传统的光刻工艺制成纳米器件，而不必依赖昂贵而复杂的电子束光刻技术。在本研究中，通过准拓扑转换，成功地从相应的氢氧根前驱体制备了微米尺寸的NiCo2O4纳米板。在从菱形LDH前驱体（空间群R$ \bar 3 $m）到立方NiCo2O4尖晶石（空间群Fd $ \bar 3 $m）的转变过程中，Co/Ni原子排列没有变化，纳米板在转变过程中保持了其初始形态。特别是，进一步研究了单个NiCo2O4纳米板内的电输运。低温范围内（T < 100k）的电传导机制可以用Mott变范围跳变模型来解释。在高温下，变范围跳变机制和最近邻跳变机制对NiCo2O4纳米板的电输运性能都有影响。这些初步结果将有助于理解这些纳米板的基本特性，并设计由NiCo2O4纳米结构制成的功能纳米器件。
Understanding the electrical transport properties of individual semiconductor nanostructures is crucial to advancing their practical applications in high-performance nanodevices. Large-sized individual nanostructures with smooth surfaces are preferred because they can be easily made into nanodevices using conventional photolithography procedures rather than having to rely on costly and complex electron-beam lithography techniques. In this study, micrometer-sized NiCo2O4 nanoplates are successfully prepared from their corresponding hydroxide precursor using a quasi-topotactic transformation. The Co/Ni atomic arrangement shows no changes during the transformation from the rhombohedral LDH precursor (space group R$ \bar 3 $m) to the cubic NiCo2O4 spinel (space group Fd $ \bar 3 $m), and the nanoplate retains its initial morphology during the conversion process. In particular, electrical transport within an individual NiCo2O4 nanoplate is further investigated. The mechanisms of electrical conduction in the low-temperature range (T < 100 K) can be explained in terms of the Mott's variable-range hopping model. At high temperatures (T > 100 K), both the variable-range hopping and nearest-neighbor hopping mechanisms contribute to the electrical transport properties of the NiCo2O4 nanoplate. These initial results will be useful to understanding the fundamental characteristics of these nanoplates and to designing functional nanodevices from NiCo2O4 nanostructures.