An electrochemical discharge machining process to produce zinc oxide (ZnO) nanoparticles (NPs) under varying voltage and duty factors has been investigated. The morphological and optical characterizations of the generated ZnO NPs were carried out. It was observed that the production rate of NPs and their size increased with an increase in voltage. The ZnO NPs produced at 120 V showed the maximum production rate larger NPs. The field-effect scanning electron microscope images of the NPs revealed a nanorod-like structure, large conical shape rods and hexagonal wurtzite-like structures. The ZnO NPs generated at 120 V and 20% duty factor presented less agglomeration of NPs compared to other NPs generated by varying electrical parameters. The crystal size of the ZnO NPs were found to vary from 31.08 nm to 50.37 nm. The ZnO NPs were also tested for use in a supercapacitor electrode, and the results showed that the specific capacitance of the electrode was 708.75 F/g at a current density of 1 A/g and a retained capacity of 90.42%.

中文翻译：

---

混合加工法合成氧化锌纳米粒子及其在超级电容器中的应用

研究了在不同电压和占空比下产生氧化锌（ZnO）纳米粒子（NPs）的电化学放电加工工艺。进行了生成的ZnO NPs的形态和光学表征。观察到NP的生产率及其尺寸随电压的增加而增加。在120 V电压下产生的ZnO NPs显示出最大的生产率，即较大的NPs。NP的场效应扫描电子显微镜图像显示出纳米棒状结构，大圆锥形棒和六方纤锌矿状结构。与通过改变电参数生成的其他NP相比，在120 V和20％的占空比下生成的ZnO NP表现出更少的NP团聚。发现ZnO NP的晶体尺寸在31.08nm至50.37nm之间变化。