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This alkali metal K2CO3 and CaCO3 as a catalyst , acetylene and acetylene and nitrogen / hydrogen as carbon vapor deposition of carbon nanofibers , the catalyst preparation method and the nano carbon fiber deposition factors were studied by SEM, TEM, XRD and HRTEM of nano-carbon fiber morphology, structure were characterized . Experiments using precursor microemulsion method and K2CO3 catalyst prepared by chemical vapor deposition of acetylene carbon nanofibers prepared . By comparing the yield found precursor prepared K2CO3 K2CO3 catalyst deposited carbon nanofibers obtained higher yield ; compare different temperature structure and morphology of carbon fibers found 600 ℃ Suitable spiral fiber growth , and 700 ℃ suitable linear fiber the growth ; in the Acetylene , fumaric acid K2CO3 potassium catalyst prepared nano-carbon fiber deposition , and found 550 ℃ deposited uniform morphology of the nano-carbon fiber , about 80 nm in diameter . Deposition temperature of 600 ℃, fiber finish is improved , there has been a small amount of carbon nanotubes , the wall is thin and smooth. Acetylene on the deposition of nitrogen was added little effect on the resulting product surface is smooth , the fiber obtained after adding hydrogen high yield ; C2H2: H2 <2: 1 , with the ratio of hydrogen increases , to increase product yield , C2H2: H2> 2: 1 , with the percentage of hydrogen increases , the product yield decreased deposition time is doubled , the yield was nearly four times the original . CaCO3 deposition experiments studied the nano-carbon fiber , 500 ℃ deposited a linear spiral nano carbon fibers and nano-carbon fiber , and carbon nano fiber produced linear fiber bundle structure of the bifurcation , crystallinity of deposited carbon is small. At 700 ℃ has also been a linear fiber and spiral fibers , carbon nanotubes also found , 700 ℃ deposited carbon is poor crystallinity , structural disorder . The carbon deposited 600 ℃ highly orderly . 600 ℃, the graphite layers along the fiber axis. 700 ℃, graphite nano-carbon fiber outer layer and the axial direction are parallel, and the inner layer fiber is confusing .
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