Nicolaescu Mircea, Vajda Melinda, Lazau Carmen, Orha Corina, Bandas Cornelia, Serban Viorel-Aurel, Codrean Cosmin
Department of Materials and Manufacturing Engineering, Faculty of Mechanical Engineering, Politehnica University Timisoara, Mihai Viteazu 1, 300222 Timisoara, Romania.
National Institute for Research and Development in Electrochemistry and Condensed Matter, Dr. A. P. Podeanu 144, 300569 Timisoara, Romania.
Materials (Basel). 2023 Apr 1;16(7):2820. doi: 10.3390/ma16072820.
A flexible electrode constructed from Fe-based amorphous ribbons decorated with nanostructured iron oxides, representing the novelty of this research, was successfully achieved in one-step via a chemical oxidation method, using a low concentration of NaOH solution. The growth of metal oxides on a conductive substrate, which forms some metal/oxide structure, has been demonstrated to be an efficient method for increasing the charge transfer efficiency. Through the control and variation of synthetic parameters, different structures and morphologies of iron oxide were obtained, including hexagonal structures with a hollow ball shape and rhombohedral structures with rhombus-like shapes. Structural and morphological characterization methods such as X-ray diffraction and SEM morphology were used on the as-synthesized composite materials. The supercapacitor properties of the as-developed amorphous ribbons decorated with FeO nanoparticles were investigated by cyclic voltammetry, galvanostatic charge discharge, and electrochemical impedance spectroscopy. The flexible supercapacitor negative electrode demonstrates a specific capacitance of 5.96 F g for the 0.2 M NaOH treated sample and 8.94 Fg for the 0.4 M NaOH treated sample. The 0.2 M treated negative electrodes deliver 0.48 Wh/kg at a power density of 20.11 W/kg, and the 0.4 M treated electrode delivers 0.61 Wh/kg at a power density of 20.85 W/kg. The above results show that these flexible electrodes are adequate for integration in supercapacitor devices, for example, as negative electrodes.
一种由装饰有纳米结构氧化铁的铁基非晶带构建的柔性电极代表了本研究的新颖之处，通过化学氧化法，使用低浓度的氢氧化钠溶液一步成功制备。在导电基底上生长金属氧化物形成一些金属/氧化物结构，已被证明是提高电荷转移效率的有效方法。通过控制和改变合成参数，获得了不同结构和形态的氧化铁，包括空心球状的六边形结构和菱形形状的菱面体结构。对合成后的复合材料使用了诸如X射线衍射和扫描电子显微镜形态学等结构和形态表征方法。通过循环伏安法、恒电流充放电和电化学阻抗谱研究了用FeO纳米颗粒装饰的非晶带的超级电容器性能。柔性超级电容器负极对0.2 M氢氧化钠处理的样品表现出5.96 F/g的比电容，对0.4 M氢氧化钠处理的样品表现出8.94 F/g的比电容。0.2 M处理的负极在功率密度为20.11 W/kg时提供0.48 Wh/kg，0.4 M处理的电极在功率密度为20.85 W/kg时提供0.61 Wh/kg。上述结果表明，这些柔性电极足以集成到超级电容器器件中，例如作为负极。
