Spinel structure Co-doped $$\hbox {ZnMn}_{{2}}\hbox {O}_{{4}}$$ nanocrystals were successfully synthesized by a hydrothermal method. The effects of Co-doping concentration on the structure and electrochemical properties of the samples were investigated. The experimental results manifest that all samples exhibit a single-phase with a tetragonal structure, and morphologies are regular hollow microspheres. Cyclic voltammetry curves for all samples are similar to a rectangular shape with symmetric nature and no obvious redox peak. Galvanostatic charge–discharge curves were triangular and symmetric. Impedance spectra revealed that $$\hbox {Zn}_{1-x}\hbox {Co}_{{x}}\hbox {Mn}_{{2}}\hbox {O}_{{4}}$$ possess low resistance. Better electrochemical properties of the $$\hbox {ZnMn}_{{2}}\hbox {O}_{{4}}$$ electrode could be obtained when the Co-doping ratio is 0.3. $$\hbox {Zn}_{0.7}\hbox {Co}_{0.3}\hbox {Mn}_{{2}}\hbox {O}_{{4}}$$ exhibits much higher specific capacitance ($$306\hbox { F g}^{-1}$$) at a scan rate of $$5\hbox { mV s}^{-1}$$, and shows excellent cycling stability and retains 98.2% of its initial capacitance after 1000 cycles. The enhanced capacitive performance in this work can be attributed to the incorporation of Co ions doped into the $$\hbox {ZnMn}_{{2}}\hbox {O}_{{4}}$$ host lattice.

中文翻译：

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共掺杂$$\hbox {ZnMn}_{2}\hbox {O}_{4}$$ZnMn2O4 空心纳米球的合成及电化学性能

通过水热法成功合成了尖晶石结构的共掺杂$$\hbox {ZnMn}_{{2}}\hbox {O}_{{4}}$$纳米晶。研究了共掺杂浓度对样品结构和电化学性能的影响。实验结果表明，所有样品均呈单相四方结构，形貌为规则的空心微球。所有样品的循环伏安曲线近似矩形，具有对称性，无明显氧化还原峰。恒电流充放电曲线呈三角形对称。阻抗谱显示$$\hbox {Zn}_{1-x}\hbox {Co}_{{x}}\hbox {Mn}_{{2}}\hbox {O}_{{4}} $$ 具有低阻力。当共掺杂比为 0.3 时，$$\hbox {ZnMn}_{{2}}\hbox {O}_{{4}}$$ 电极可以获得更好的电化学性能。$$\hbox {Zn}_{0.7}\hbox {Co}_{0.3}\hbox {Mn}_{{2}}\hbox {O}_{{4}}$$ 表现出更高的比电容（ $$306\hbox { F g}^{-1}$$) 在 $$5\hbox { mV s}^{-1}$$ 的扫描速率下，表现出优异的循环稳定性并保持其初始电容的 98.2% 1000 次循环后。这项工作中增强的电容性能可归因于将 Co 离子掺入 $$\hbox {ZnMn}_{{2}}\hbox {O}_{{4}}$$ 主晶格中。1000 次循环后其初始电容的 2%。这项工作中增强的电容性能可归因于将 Co 离子掺入 $$\hbox {ZnMn}_{{2}}\hbox {O}_{{4}}$$ 主晶格中。1000 次循环后其初始电容的 2%。这项工作中增强的电容性能可归因于将 Co 离子掺入 $$\hbox {ZnMn}_{{2}}\hbox {O}_{{4}}$$ 主晶格中。