Preparation And Characterization Of Branched Carbon Fibers

Carbon fiber is a kind of materials with excellent performance, which possesses many unique properties, such as high specific strength, high specific modulus, high conductivity and high specific surface area. It has great potential on many applications such as catalyst and catalyst carrier, electric double layer capacitor electrode, and adsorbents. Compared with other forms of carbon fiber, VGCF has special structure and properties, and the research on its morphology and growth pattern has been extensively investigated.In this article, carbon fibers were formed under three different conditions. Firstly, the influence of different substrate materials on the growth of carbon fibers was discussed. Graphite, ceramic, and titanium dioxide plate with uniform porous structure of around 100 nm were used as substrate materials respectively. The morphology was characterized by scanning electron microscope. Carbon fibers prepared from different substrates demonstrate great differences in morphology and yield. Carbon fibers prepared from ceramic and graphite substrate with higher yield were mainly linear filaments, and they were in both-way growth pattern but with different diameters and length. Carbon fibers prepared from titanium dioxide plates with more uniform morphology and followed bottom growth pattern due to catalysts embedded inside pore structures.Cupric nitrate with plate-like structure was produced by a hydrothermal method, and then was used as catalyst precursor to synthesize carbon fiber arrays by chemical vapor deposition method, in which hydrogen and acetylene were employed as pre-treatment gas and carbon source gas, respectively. Experimental results demonstrate that reaction temperature and hydrogen have important effects on the formation of carbon fiber arrays.