β-Nickel Hydroxide Nanosheets and Their Thermal Decomposition to Nickel Oxide Nanosheets

Powders of single-crystalline β-nickel hydroxide (β-Ni(OH)2) nanosheets with the hexagonal structure have been successfully synthesized by the hydrothermal method at 200 °C using nickel acetate as the nickel source and aqueous ammonia as both an alkaline and complexing reagent. The yields of β-Ni(OH)2 nanosheet powders were higher than 92.4%. This method is simple and low-cost for large-scale production of powders of single-crystalline β-Ni(OH)2 nanosheets. Single-crystalline nickel oxide (NiO) nanosheets have been synthesized by thermal decomposition method at 400 °C for 2 h using single-crystalline β-Ni(OH)2 nanosheets as the precursor. The sheet shape of β-Ni(OH)2 was sustained after thermal decomposition to NiO. The as-prepared products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), differential scanning calorimetric analysis (DSC), and thermogravimetric analysis (TG).