电沉积法制备Cu(OH)_(2)/Ni-Co-S复合电极及储能特性研究

Electrodeposition Preparation of Cu(OH)_2/Ni-Co-S Composite Electrode for Energy Storage

本文采用两步电沉积技术,以泡沫铜为基底,原位制备了Cu(OH)_(2)/镍钴双金属硫化物(Ni-Co-S)复合电极材料。先采用恒电流沉积技术将泡沫铜表面氧化,得到Cu(OH)_(2),泡沫铜同时作为电极基底和铜的唯一来源,再通过恒电位沉积,将Ni-Co-S均匀覆盖在Cu(OH)_(2)表面。Cu(OH)_(2)一方面作为活性电极组分参与氧化还原反应,同时作为底层材料,为顶层Ni-Co-S的沉积提供较大的沉积空间,进而形成了更丰富的电化学活性位。基于这种原位电沉积技术以及Cu(OH)_(2)与Ni-Co-S组分的协同作用,Cu(OH)_(2)/Ni-Co-S复合电极表现出增强的赝电容特性,在2mA·cm^(-2)的放电电流密度下,比容量为4.88 F·cm^(-2),库伦效率为88.12%,5000次充放电循环后,比容量保持在初始值的86.38%。

In this paper,a two-step electrodeposition technique was employed to in-situ prepare Cu(OH)_2/Ni-Co-S composite electrode material on copper foam.First,Cu(OH)_(2) was formed on the surface of copper foam by constant current deposition.Copper foam served as both the electrode substrate and the only source of copper.Then,uniform deposition of Ni-Co-S on the Cu(OH)_(2) surface was achieved by constant potential deposition.Therefore,on the one hand,Cu(OH)_(2) participated in the redox reaction as an active electrode component,on the other hand,as the underlying material,it provided ample deposition space for the Ni-Co-S layer,thus forming a more abundant electrochemical active site.Based on the in-situ electrodeposition technique and the synergistic effect of Cu(OH)_(2) and Ni-Co-S components,the Cu(OH)_2/Ni-Co-S composite electrode exhibited enhanced pseudocapacitive characteristics.At a discharge current density of 2mA/cm^(2),the specific capacitance was 4.88F/cm^(2) with a coulombic efficiency of 88.12%.Moreover,after 5000 charge-discharge cycles,the specific capacitance retained 86.38% of its initial value.