Effect of dodecyl sulfate anions on the electrochemical performances of Zinc-Aluminum-hydrotalcite as anode material for Zinc/Nickel secondary batteries

• Zn-Al-C12H25OSO3 layered double hydroxides (LDH-DS) was prepared by anion exchange method.
• The prepared LDH-DS was used for Zn/Ni secondary battery.
• LDH-DS exhibits a better corrosion inhibition and higher hydrogen evolution over-potential.
• LDH-DS reveals higher specific discharge capability and superior electrochemical cycle performances.

Zn-Al-CO3 layer double hydroxides (LDHs) are synthesized by a simple hydrothermal method, followed by the anion-exchange processes to intercalate dodecyl sulfate (DS) anions into LDHs interlayer. The structures and morphologies of the as-prepared samples are characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results illustrate all samples have typical layer structure of LDHs, and the LDHs intercalated with dodecyl sulfate (LDH-DS) has better crystallization and smoother surface compares to conventional LDHs. Subsequently, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Tafel and galvanostatic charge/discharge tests on LDH-DS electrode are performed. The results demonstrate that the exchanged sample has superior electrochemical performances in comparison with LDH-CO3, such as superior cycle stability, higher specific discharge capacity and utilization ratio of the active material. The specific discharge capacity of the LDH-DS electrode reaches 375 mAh g−1 and exhibits excellent stability after 150 cycles.