CQE - Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
LMGP, Univ. Grenoble Alpes, CNRS, F-38000 Grenoble, France.
Sci Rep. 2017 Jan 4;7:39980. doi: 10.1038/srep39980.
Consecutive layers of Ni(OH) and Co(OH) were electrodeposited on stainless steel current collectors for preparing charge storage electrodes of high specific capacity with potential application in hybrid supercapacitors. Different electrodes were prepared consisting on films of Ni(OH), Co(OH), NiCo(OH) and layered films of Ni(OH) on Co(OH) and Co(OH) on Ni(OH) to highlight the advantages of the new architecture. The microscopy studies revealed the formation of nanosheets in the Co(OH) films and of particles agglomerates in the Ni(OH) films. Important morphological changes were observed in the double hydroxides films and layered films. Film growth by electrodeposition was governed by instantaneous nucleation mechanism. The new architecture composed of Ni(OH) on Co(OH) displayed a redox response characterized by the presence of two peaks in the cyclic voltammograms, arising from redox reactions of the metallic species present in the layered film. These electrodes revealed a specific capacity of 762 C g at the specific current of 1 A g. The hybrid cell using Ni(OH) on Co(OH) as positive electrode and carbon nanofoam paper as negative electrode display specific energies of 101.3 W h g and 37.8 W h g at specific powers of 0.2 W g and 2.45 W g, respectively.
连续的 Ni(OH) 和 Co(OH) 层在不锈钢集电器上电沉积，用于制备具有高比容量的电荷存储电极，潜在应用于混合超级电容器。制备了不同的电极，包括 Ni(OH)、Co(OH)、NiCo(OH)薄膜和 Ni(OH)在 Co(OH)上和 Co(OH)在 Ni(OH)上的层状薄膜，以突出新结构的优势。显微镜研究表明，Co(OH)薄膜中形成了纳米片，Ni(OH)薄膜中形成了颗粒团聚体。在双氢氧化物薄膜和层状薄膜中观察到重要的形态变化。电沉积的薄膜生长受瞬时成核机制的控制。由 Ni(OH)在 Co(OH)上组成的新结构显示出氧化还原响应，其特征是在循环伏安图中存在两个峰，这归因于层状薄膜中存在的金属物种的氧化还原反应。这些电极在特定电流为 1 A g 时表现出 762 C g 的比容量。使用 Ni(OH)在 Co(OH)上作为正极和碳纳米泡沫纸作为负极的混合电池在特定功率为 0.2 W g 和 2.45 W g 时显示出 101.3 W h g 和 37.8 W h g 的特定能量。
