A facile preparation of 3D flower-shaped Ni/Al-LDHs covered by β-Ni(OH)2 nanoplates as superior material for high power application

• Published in: Chinese journal of chemical engineering 2019-10, Vol.27 (10), p.2526-2534
• Main Authors: Khan, Abrar, Senthil, Raja Arumugam, Pan, Junqing, Sun, Yanzhi
• Format: Article
• Language: English
• Subjects: Cathode material; Nanostructures; Nickel hydroxide; Ni–MH batteries; Ultrafast charge–discharge
• ISSN: 1004-9541; 2210-321X
• DOI: 10.1016/j.cjche.2019.01.025

In the present study, we propose a novel electrode material of β-nickel hydroxide covering nickel/aluminum layered double hydroxides via a facile complexation–precipitation method. The as-obtained materials with 3-dimensional nanostructures are further utilized as highly capable electrode material in nickel–metal hydride batteries. The electrochemical test results demonstrated the β-nickel hydroxide covering nickel/aluminum-layered double hydroxides with 28% of β-nickel hydroxide provided a superior specific capacity value of 452 mA·h·g−1 in a current density of 5 A·g−1 using 6 M KOH as electrolyte as compared with other materials. In addition, the optimized sample displays an outstanding cyclic stability along with a huge specific capacity value of 320 mAh·g−1, and very small decay rate of 3.3% at 50 A·g−1 after 3000 cycles of charge/discharge test. These indicate that the newly designed material with nanostructures not only provides an efficient contact interface between electrolyte and active species and facilitates the transport of electrons and ions, but also protects the 3-dimensional nickel/aluminum layered double hydroxides, achieving a high specific capacity, fast redox reaction and excellent long-term cyclic stability. Therefore, the β-nickel hydroxide covering nickel/aluminum layered double hydroxides with superior electrochemical performance is predictable to be a gifted electrode material in nickel–metal hydride batteries. [Display omitted]