We report that two-dimensional (2D) hexagonal nickel oxide (NiO) nanosheets have been successfully synthesized using the electrolysis of nickel plate as the anode in deionized water. The electrolysis processes first produced 2D nickel hydroxide (Ni(OH)₂) nanosheets, which were transformed to 2D NiO by calcination. Contrary to the classical crystallization mechanism, contiguous SEM observations revealed that the Ni(OH)₂ were produced via a multistep oriented attachment (MOA) mode, in which the [Ni(OH)₆]⁴⁻ coordination octahedron serves as the building block. Hydrothermal experiments further showed that the technique can be applied to the synthesis of 3D Ni(OH)₂ nanoflowers with the aid of introduced Ni(OH)₂ nanosheets. A growth mechanism based on the selective-surface adsorption and intercalation of nitrate ions (NO₃⁻) and hydroxyl ions (OH⁻) as well as the adsorption of free ammonia molecules (NH₃), was proposed. The crystal morphologies and thickness can be controlled by a charging magnetic field, suggesting that the crystal growth mechanisms are dominated by micromechanics such as the magnetic dipole force, Van der Waals force and magnetic force.

中文翻译：

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电场，温度和磁场作用下可 电解合成NiO纳米晶的电解方法和Ni（OH）₂前体的自组装机制†

我们报告二维（2D）六边形氧化镍（NiO）纳米片已经成功地合成了使用去离子水中的镍板作为阳极的电解。电解过程首先产生2D氢氧化镍（Ni（OH）₂）纳米片，通过煅烧将其转变为2D NiO。与经典的结晶机制相反，连续的SEM观察表明Ni（OH）₂是通过多步定向附着（MOA）模式产生的，其中[Ni（OH）₆ ] ^4-配位八面体用作构造单元。水热实验进一步表明该技术可应用于3D Ni（OH）₂的合成引入Ni（OH）₂纳米片的纳米花。基于所述选择性表面吸附和硝酸根离子（NO的嵌入甲生长机理₃ ^-和氢氧根离子（OH） - ^），以及游离氨分子（NH的吸附₃），中提出的。晶体的形貌和厚度可以通过充电磁场来控制，这表明晶体的生长机理主要由诸如磁偶极力，范德华力和磁力等微力学控制。