Abstract Cobalt doped zinc oxide (Zn1-xCoxO; x = 0, 0.05, 0.10, 0.15) samples were synthesized using co-precipitation method. The Co doped ZnO nanoparticles showed the maximum solubility limit. The XRD patterns confirm the hexagonal type wurtzite structure without secondary phase in Co substituted ZnO samples. The particle size was studied using transmission electron microscope (TEM) and grain size estimated using scanning electron microscope (SEM). We report the study of temperature dependence of conductivity on ZnO and Co doped ZnO nanoparticles. It is found that at a higher temperature range (above 470 K) thermally activated type of conduction is in dominance with the lower temperature range of conduction in which donor carrier hopping mechanism is dominated. DC conductivity result shows the reduction nature for cobalt doped ZnO. The obtained results are discussed on basis of potential barrier, donor concentration, point defects and adsorption–desorption of oxygen. Cobalt substitution increases resistivity, reduces grain growth, lower particle size and increase in activation energy. Detailed mapping of two regions of electrical conductivity is done to understand the activation energy mechanisms prevailing in cobalt doped ZnO.

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钴掺杂对氧化锌纳米粒子电导率的影响

摘要 采用共沉淀法合成了钴掺杂氧化锌（Zn1-xCoxO；x = 0, 0.05, 0.10, 0.15）样品。Co掺杂的ZnO纳米颗粒表现出最大溶解度极限。XRD 图案证实了 Co 取代的 ZnO 样品中没有第二相的六方型纤锌矿结构。使用透射电子显微镜 (TEM) 研究粒径，使用扫描电子显微镜 (SEM) 估计晶粒尺寸。我们报告了电导率对 ZnO 和 Co 掺杂的 ZnO 纳米粒子的温度依赖性的研究。发现在较高温度范围（高于 470 K），热激活类型的传导占主导地位，而较低温度范围的传导占主导地位，其中供体载流子跳跃机制占主导地位。直流电导率结果显示了钴掺杂 ZnO 的还原性质。所得结果基于势垒、供体浓度、点缺陷和氧的吸附-解吸进行了讨论。钴替代增加电阻率，减少晶粒生长，降低颗粒尺寸并增加活化能。完成了两个导电区域的详细映射，以了解钴掺杂 ZnO 中普遍存在的活化能机制。