Ruijuan Wang

Zn–Al layered double oxides as high-performance anode materials for zinc-based secondary battery

In this work, Zn–Al layered double oxides (Zn–Al-LDO) were prepared via a facile hydrothermal method, followed by calcination treatment in an air atmosphere, and evaluated as anode materials of Zn/Ni batteries. The morphology and structure of as-prepared Zn–Al-LDO and its precursor Zn–Al layered double hydroxide (Zn–Al LDH) were investigated through Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Compared to the Zn–Al-LDH precursor, Zn–Al-LDO possesses higher discharge capacity, better reversibility and longer cycle life. The discharge capacity of Zn–Al-LDO remains about 460 mA h g−1 after 1000 cycles. In particular, good rate performance can be observed for a Zn–Al-LDO electrode. The superior properties could be ascribed to improved charge conductivity and the absence of carbonate anions, which make migration of hydroxyl anions smooth to meet the requirements of the electrochemical reaction of the electrode.

Silver nanoparticle deposited layered double hydroxide nanosheets as a novel and high-performing anode material for enhanced Ni–Zn secondary batteries

Simple and facile processes to produce silver nanoparticle deposited layered double hydroxide (Ag-LDH) nanosheets are reported. By a wet chemical reduction method in an aqueous AgNO3 solution, silver ions can be readily reduced to metallic silver nanoparticles and incorporated evenly on the surface of 2D LDH nanosheets. Structure and morphology analysis of the Ag-LDH composites is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Ag-LDH composites are characterized electrochemically proving their exceptional cyclability and high discharge capacity. Electrochemical impedance spectroscopy (EIS) and four-point probe conductivity measurements show that silver modification decreases the charge transfer resistance of the anode, and improves the conductivity of the active material, which boosts the electrochemical performance of Ag-LDH composites. These newly designed Ag-LDH nanosheets may offer a promising anode candidate for high-performance Ni–Zn secondary batteries and other zinc battery applications.