Hexagonal mesoporous MgO nanosheets with a side length of 250 nm and specific surface area of 181.692 m(2)/g were fabricated by a three-step process. Firstly, MgO powders were obtained by sintered Mg5(OH)2(CO3)4⋅4H2O, which was synthesized by a wet precipitation process using ammonium hydrogen carbonate as precipitants. Secondly, the above-MgO were distilled 2 h in a three-necked bottle with condenser device. Lastly, we annealed the distilled-MgO at 500-800 °C to form mesoporous MgO nanosheets. We found the pore size distribution and the thicknesses of nanosheets were determined by the distillation process in step 2 and annealed temperature in step 3. By optimizing the experimental parameters, the mesoporous dis-MgO annealed at 600 °C displayed uniform hexagonal structure with the largest pore volume (0.875 cm(3)/g) and highest BET surface area (181.692 m(2)/g), as well as the maximum adsorption capability of 1684.25 mg/g for Ni(II).
Keywords: Adsorption; Distillation process; High surface area; Mesoporous; MgO nanosheets; Ni(II).
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