Microstructural Modification of NiAl Layered Double Hydroxide Electrodes by Adding Graphene Nanosheets and Their Capacitative Property

摘要

NiAl layered double hydroxide (LDH) composite electrodes containing various contents of graphene nanosheets (GNS) were prepared by a hydrothermal method. The micro-structure and morphological properties were examined by FE-SEM, FE-TEM, XRD, and FTIR. Electrochemical analysis was also carried out by cyclic voltammetry, impedance, and cycle life measurement. The as-prepared composite that contained 500 mg of graphene (denoted as NiAl/G-50) achieved the highest specific capacitance of 1147 F/g among the various NiAl LDH/GNS composites. Besides, the NiAl LDH/GNS composite exhibited the lower diffusion resistance, improved rate capability, and good cyclic stability (83% of initial capacitance after 2000 cycles). Considering the morphological data and the improved capacitative properties together, we concluded the synthesized NiAl LDH/GNS composites would be a promising electrode material for supercapacitors.