Synthesis of Hollow Spherical Zinc-Aluminum Hydrotalcite and Its Application as Zinc Anode Material

A simple urea hydrothermal method was used to synthesize hollow spherical zinc-aluminum hydrotalcites (ZAL-H) with the particle size of about 6.7–9.8 μm. The studies on different synthetic conditions have shown that the amount of urea and the type of solution system play important roles on the morphology and particle size of ZAL-H. X-ray diffraction (XRD) patterns indicate that the material has characteristic diffraction peaks of zinc-aluminum hydrotalcite. The specific surface area and pore size analysis (BET) indicate that the material has a uniform and narrow distribution of pore diameter of 3.682 nm and a specific surface area of 49.09 m2 g−1. As negative electrode material for zinc-nickel battery, the ZAL-H electrode exhibits a significantly enhanced discharge specific capacity compared to most previously reported electrodes based on zinc-aluminum hydroxides. The average discharge special capacity is 393.342 mAh g−1 during the whole charge/discharge process (1050 cycles), the discharge efficiency is up to 97.34%, and the capacity retention rate is as high as 95.37%. Therefore, the ZAL-H is an excellent electrode active material and can be potentially applied to the energy storage/conversion devices.