Preparation Of Nickel Nano-network Structure Thin Film Based On Electrodepositon

Nano-materials have many available features which large solids do not have due to its size. In recent years, it has great application potential in fields like catalysis, activations, sensing and surface enhanced scattering. Among them, nano-network thin film materials have a great surface area and therefore have a higher electro-catalytic activity. It applications are important in areas such as catalysis and separation science. Therefore, the exploration of this kind of materials has significant meanings.At present, the preparation of nano-materials has been more mature. However, researches on some new simple and effective preparation methods are still of great significance. Among a variety of methods for preparing nano-materials, electrodeposition has the following advantages: (1) can prepare a variety of single metal or alloy materials; (2) simple equipment, low cost; (3) low barriers need to overcome technical; (4) have little restrictions by size. Based on electrodeposition, we prepared a new type of nickel nano-network thin film structural materials. The method is simple, low cost, and is expected to be widely used. We exported the process of electrodeposition, studied the crystal growth mechanism of nickel nano-network structure, and do research on the surface wetting behavior. Following conclusions are achieved:Firstly, by adjusting the electrodeposition bath composition and deposition process parameters, we found that a steady nano-network structure can be fabricated. When join additive amine hydrochloride to the bath solution, we can change the surface micro-structure from nickel layer into a nano-network structure. The study shows that small changes in temperature have little impact on the structure and 40~50℃are the suitable range; a higher current density (5 A / dm2) is needed for the nano-net structure; with the extension of deposition time, there was little change for the surface structure.Secondly, section observation confirmed that this kind of nickel nano-network thin film has certain porosity. XRD spectrum analysis and grain size calculations found that the grain size obtained basically the same under different deposition time. Compared with the value calculated from SEM photographs, we found the two radius values are close to each other. Therefore, we infer the structure of each one behalf structure is a dendritic grain and the thin film is layer of sediments.Thirdly, by using pulse plating, a more bulky structure of a stable nano-network structure and be prepared compared with DC system. And smaller pulse current density was needed; pulse frequency has little inference on the morphology of deposits; pulse duty cycle has a significant effect on morphology, with the decreases of the duty cycle, the structure observed from SEM increased and the grain size calculated by XRD continued to grow.Finally, the results of surface wetting properties test showed that nano-network structure with a branched surface has a larger wetting angle than smooth surface of nickel deposits. The wetting angle values improved with the increasing of grain size as well.