Research On Preparation Of Ag/C Composite Nanofibers And Their Conductive Properties

With the development of the material industry, the need for compositematerial is larger. Because of the light density, excellent mechanical propertiesand other properties, carbon fibers are widely used in many fields. Since thedevelopment of the carbon material is early, the development of carboncomposite material is also fast. Among them, silver-decorated carbon nanofibersare widely used in biomedicine, optical absorption, catalytical industry and so on.Currently, the silver-decorated carbon nanofibers that have some drawbacks arethick, less uniformity, and the fibers are not fully coated by silver particles. Theyare mainly used in catalytic industry, biological sterilization, etc., and less usedin conductive area.In this article, how to coat the carbon nanofibers with silver by electrolesssilver plating to improve their conductive properties will be researched. And thenthe material will be analyzed by the methods of SEM, EDS and XRD which areused to analyze the surface morphology, element and the phase on the surface ofthe material. The four points probe method is used to analyze the conductiveproperties. What more is TGA which is used to analyze the weight of the materialis heavier or lighter.In this article, two kinds of reductive system, which are glucose-silverammonia solution and ascorbic acid-silver nitrate solution, will be researchedabout the result of the silver coated on the carbon nanofiber s. And then how thetemperature and time which is used when the fibers are heated in the SnCl2/HClsolution work on the result of the silver coated on the carbon nanofiber s will betalked. What’s more is adding some other substances, such as nitrates, chlorides,organic and dilute nitric acid, working on the effect of the silver coated on thecarbon nanofibers. When the time and temperature are40℃,60min and90℃,30min, respectively. Carbon fibers are coated by silver completely. By addingnickel nitrate in the glucose-silver ammonia solution system, carbon nanofibersare not only completely coated, but also the coat ing is smooth and uniform.In this article, adding complex agent in the ascorbic acid-silver nitrate solution system are talked about. The amount of mixed complex agent A, theconcentration of ascorbic acid and the silver nitrate are talked about. The resultsindicate that adding mixed complex agent A is benefit for silver coated on thecarbon nanofibers. When the range of the amount of the mixed complex agent Aused is1-2.5mL, the carbon nanofibers can be coated by silver completely.In this article, the universal applicability of the silver plating liquid above istalked about. It is used in other carbon nanofibers, carbon materials and othersubstance. As a result, they all can be coated by silver except CNTs. The silverparticles on the copper are very uniform. And the red color of copper is coveredby silver which is grey-white.