Abstract In this work, to enhance supercapacitor research performance, we have prepared two different types of ferrites as CoFe2O4 and NiFe2O4 nanoparticles by two different routes, such as co-precipitation followed by hydrothermal method and facile hydrothermal method for the first time. In order to study the structural, morphological, and elemental composition of the fabricated ferrite electrodes, various characterization studies have been carried out, such as XRD, Raman, FESEM, EDS, HRTEM, BET, and XPS analysis. N2 adsorption-desorption results reveal that the hydrothermal assisted NiFe2O4 electrode shows a high surface area (109.3 m2/g) and pore size (43.4 nm) than compared with CoFe2O4 (78.5 m2/g and 21.2 nm). The electrochemical studies have been carried out for the electrodes using 1M H2SO4 as electrolyte and graphite sheet as a current collector through three-electrode and two electrode systems, respectively. A maximum specific capacitance of 466 F g-1 at a current density of 1 A g-1 and 280 F g-1 at a current density of 0.5 A g-1 were obtained for the nickel ferrite nanoplates prepared via one-step hydrothermal method using three-electrode and two electrode systems, respectively. Moreover, the assembled symmetric NiFe2O4 supercapacitor delivers a high energy density (10 Wh Kg-1) at 0.5 A g-1 and power density (2500 W Kg-1) at a current density of 5 A g-1. Besides, the NiFe2O4 symmetric supercapacitor device exhibits 100 % of specific capacitance retention sustained up to 10000 cycles and 99 % of Columbic efficiency.

中文翻译：

---

用于高性能储能应用的钴和镍铁氧体基柔性电极的设计和制造

摘要 在这项工作中，为了提高超级电容器的研究性能，我们首次通过共沉淀后水热法和简易水热法两种不同的途径制备了两种不同类型的铁氧体，即 CoFe2O4 和 NiFe2O4 纳米颗粒。为了研究制造的铁氧体电极的结构、形态和元素组成，已经进行了各种表征研究，例如 XRD、拉曼、FESEM、EDS、HRTEM、BET 和 XPS 分析。N2 吸附-解吸结果表明，与 CoFe2O4（78.5 m2/g 和 21.2 nm）相比，水热辅助 NiFe2O4 电极显示出更高的表面积（109.3 m2/g）和孔径（43.4 nm）。分别通过三电极和两电极系统对使用1M H2SO4作为电解质和石墨片作为集流体的电极进行了电化学研究。一步水热法制备的镍铁氧体纳米片在1 A g-1的电流密度下获得的最大比电容为466 F g-1，在0.5 A g-1的电流密度下获得了280 F g-1的最大比电容分别使用三电极和两电极系统。此外，组装的对称 NiFe2O4 超级电容器在 0.5 A g-1 时提供高能量密度（10 Wh Kg-1）和在 5 A g-1 电流密度下提供高功率密度（2500 W Kg-1）。此外，NiFe2O4 对称超级电容器装置表现出 100% 的比电容保持率，持续高达 10000 次循环和 99% 的 Columbic 效率。