수산화 코발트 나노시트가 슈퍼 커패시터용 니켈 알루미늄 층상이중수산화물에 미치는 영향

Abstract

In recent years, many cities, such as Beijing and Seoul, have been plagued by increasingly serious haze issues, for which high levels of automobile exhaust are one of the chief culprits. Therefore, it is a matter of urgency to promote the development of environmentally friendly electric vehicles equipped with new and clean energy storage components to solve the increasingly serious energy and environmental problems. The supercapacitor, an energy storage component, is the focus of research at present. It is known for its incomparable advantages, such as long-circle stability, high power density and energy density, and low cost. With this research focus, the development of electrode material with excellent electrochemical properties is regarded as an important project. Ni-Al layered double hydroxide (LDH) shows excellent supercapacitor performance due to its unique spatial structure, and it has attracted considerable research interest in the field of materials science. Taking this as the starting point in this paper, after conducting an extensive literature research, we created a three-dimensional (3D)-network-structured Ni-Al LDH composite electrode material with a large specific surface area (SSA) and high specific capacities that has very good development prospects. In this paper, we first used Ni-Al double hydroxide electrode material prepared by the hydrothermal method to produce Ni-Al double hydroxide/nickel foam (NF) composite electrode material with a 3D network structure and tested its electrochemical properties. It was discovered that the material has a specific capacity of up to 726.7 F·g-1 with a good rate capacity, and its specific capacity can reach a 70% retention rate at the current density of 20A/g after 1,000 cycles. Then, we prepared a composite electrode of Ni-Al double hydroxide and cobalt hydroxide by the electrochemical deposition method with Ni-Al double hydroxide as a base. These two kinds of electrode materials were characterized from the aspects of structure and morphology, and the electrochemical capacitance performance was investigated from the perspective of improving conductivity and adhesion. As the results show, a specific capacity of 1460.2 F·g-1 was found at the current density of 2 A/g. Finally, we investigated the properties of the materials from the perspective of improving the loading amount of active materials in the electrode material. The results show that when the loading amount reached a certain level, the electrode material retained a high specific capacity and excellent cycling stability, and the retention rate of specific capacity was 88.5% at the current density of 20 A·g-1 after 3,000 cycles.