Electroforming Nickel-based Functional Based On The Porous Template

Traditional electroforming technology plays an important role in the micro-precisionprocessing industry, and society puts forward more and more demands for nano functionaldevices with the development of the microelectronics industry. Traditional electroformingtechnology combined with nanotechnology can fabricate more nano functional devices tomeet the needs of the community.The electroformed Ni from sulfamate solution has no in-ternal stress and has high mechanical strength and toughness and the electroforming technol-ogy is used to manufacture complex products and the fine surface of complex parts. In thispaper, a highly ordered prepatterned Ni stamps and a high specific surface area porous Nicurrent collector have been fabricated by combining the electroforming Ni process with an-odic aluminum oxide template and porous etching aluminum, and the properties were evalu-ated. The details are as follows:To meet the needs of nano array devices on the substrate, imprinting is a simple way tofabricate ultra-thin ordered anodic aluminum oxide template, which does not require expen-sive equipment and is suitable for large-scale production. However the traditional method offabricating Ni stamps is complex and requires expensive equipments. In present thesis, theordered Ni stamps were obtained from the techniques such as electroless plating and electro-forming which were widely used for industrial and commercial for decades, and a ordered ul-tra-thin anodized aluminum template was prepared by imprinting method. The conical AAOtemplate were fabricated by combining the conical opening with one step short-time anodiza-tion. The Ni stamps with a good mechanical properties were electroformed on the conicalPAA template and the electroless deposition of Ni were performed for offering the conductivelayer. A highly ordered anodic aluminum oxide film with interpore distance of450nm hasbeen fabricated from prepatterned Al using the Ni stamp combined hard stamping technology.In order to simplify the steps of preparation process, hexagonal convex Ni stamps were fabri-cated by one step which directly used the ordered concave of high-purity aluminum film and(100) plane aluminum and a relatively orderly PAA film were obtained from the orderly pat-terned-aluminum by imprinting technology, with above stamp. Electrochemical capacitors are currently receiving increasing consideration due to their long-term cycling stability and high charging/discharging rates. In order to obtain a high area specific capacitance, it should be combine the optimized structure of the three-dimensional collector with the high-effective utilization of the active electrode layer. In present thesis, a three-dimensional interconnected sub-micron Ni pillar array were fabricated by electroform-ing Ni on the anodized porous etched aluminum, the thin nickel hydroxide film formed on the surface of porous Ni collector using anodic oxidation process by CV cycles. The areal capaci-tance (scan at10mV s-1) of the hierarchically porous nickel hydroxide-nickel electrode from10min-anodized etched aluminum was2.9and19times of that of electrodes from etched and smooth aluminum, respectively. The anodizing time had a significant influence on the mor-phology of the porous Ni collector. The capacitance cycle stability measurement results indi-cated that the stability of the composite electrode material had a good stability. The capaci-tance cycle stability measurement results indicated that96%of the initial capacitance was re-tained after5000cycles at scan rate of100mV s-1. The high areal capacitance was685mF cm-2and the large volumetric capacitance wais152F cm-3at a scan rate of1mV s-1.