Facile Fabrication of Nickel Aluminum Layered Double Hydroxide/Carbon Nanotube Electrodes Toward High-Performance Supercapacitors

Abstract

The electrode, as one of the key components in supercapacitors, has a pivotal effect on the overall performances. In this work, a series of composite electrode materials are proposed via the combination of nickel aluminum layered double hydroxides (NiAl-LDHs) and carbon nanotubes (CNTs). To begin with, materials with different ratios of the two compositions are fabricated with a coprecipitation method. After that, various characterization methods indicate that the NiAl-LDH/CNT composites exhibit an irregular thin platelet structure with a well-constructed conductive network inside. Furthermore, the effect of the CNT ratio on the electrochemical property is subsequently investigated, which proves that the conductive network of CNTs is beneficial for the transport of the electrons and strengthens the platelet structure. The results show that when the amount of CNTs reaches 1.5 wt %, it can yield a high specific capacitance of 2447 F g^-1 at 2 A g^-1, with a good cycling stability of 90.1% after 2500 cycles, indicating high application potential in positive electrodes of pseudocapacitors. The synergistic effects of NiAl-LDHs and CNTs are thought to be the main reasons for the good properties of NiAl-LDHs/CNTs composites.