近二维结构的六边形金属镍纳米片的水热合成

片状二维镍纳米材料具有较高的形状各异性,在催化、磁记录以及生物探测方面具有重要的应用价值,因此寻找一种简单,成本低的方法制备表面无活性剂的片状镍纳米材料显得尤为重要。在没有有机表面活性剂和形貌控制剂的条件下,在氟掺杂氧化铟锡(FTO)导电玻璃表面,通过水热制备得到金属镍纳米薄片。系统地研究了反应条件对产物形貌的影响,发现镍源、氢氧化钠、氨水的浓度以及反应温度对纳米镍的形貌有较大的影响。只有在合适的氨水和氢氧化钠浓度共同存在下,才能获得具有较大的特征长度以及较薄的近二维结构的六边形镍金属钠米薄片。经过条件优化,制备得到的厚度约为10 nm,横向特征长度超过1μm金属镍纳米薄片。经过分析认为,体系的p H值及温度影响了反应速度,最终导致产物的形貌受到影响,在p H值约为10的条件下,氨水对镍离子的络合作用对镍纳米薄片的二维生长具有一定的促进作用。

Hydrothermal Synthesis of an Approximate Two-Dimensional Hexgonal Nickel Nanoplatelets

2D platelet like nickel nanomaterials have high anisotropy with the morphology, and have the significant application on the catalysis, magnetic recording, energy source and biological detection field. It is important to search a simple, low cost method to prepare platelet like nickel nanomaterials without any surfactant. Without any organic surfactant and other morphology control agent, thin nickel nanoplatelets were successfully prepared on the fluorine-doped tin oxide(FTO) under the hydrothermal condition. The influence of synthetic conditions on the morphology of the nanoplatelets was investigated. It is found that the concentration of nickel salt, sodium hydroxide, and ammonia and the reaction temperature have apparent influences on the morphology of the nickel nanoplatelets. The ideal nickel nanoplatelets with large lateral size and small thickness can be obtained only under optimal concentrations of both sodium hydroxide and ammonia together. Approximate two-dimensional(2D) hexgonal thin nickel nanoplatlets with a characteristic thickness of about 10 nm and the lateral feature width of about 1 μm were obtained under optimal synthetic conditions. The pH value and the reaction temperature affect the reaction speed, and finally the morphology of the nanoplatelets. At pH 10, the complexation of ammonia to the nickel ion can facilitate the 2D growth of nickel nanoplatelets.