Self-assembly of exfoliated layered double hydroxide and graphene nanosheets for electrochemical energy storage in zinc/nickel secondary batteries

In this work, the Zn-Al layered double hydroxide (Zn-Al LDH) is exfoliated. Ambient temperature ion exchange and chemical exfoliation route have been developed to synthesize the exfoliated layered double hydroxide/graphene compounds (Exfoliated LDH/G). The as-prepared Exfoliated LDH/G nanocomposites demonstrate no obvious impurity and good morphology, being characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). Here we intensively study the electrochemical performances of Exfoliated LDH/G and pure LDH electrodes for Zn-Ni secondary battery. It was found that the as-prepared Exfoliated LDH/G here exhibits higher and wide discharge voltage plateaus due to the well electrical conductivity and lower self-corrosion, which could promote charge-transfer of the exfoliated LDH. The preliminary results show that the Exfoliated LDH/G displays superior Zn-Ni secondary battery performance with outstanding reversible capacity, prominent cyclic performance (343 mA h g−1 after 1200 cycles at 1 C), highlighting the practicability of the self-assembly Exfoliated LDH/G for maximum anodic utilization of exfoliated LDH for power storage in Zn-Ni secondary battery.