电沉积Fe-P合金镀层催化碳纤维石墨化研究

研究了电沉积Fe-P合金镀层对碳纤维的催化石墨化效果以及镀层组成对催化石墨化温度的影响.采用X-射线衍射、拉曼光谱及扫描电子显微镜等方法表征了空白样碳纤维与含Fe-P合金镀层碳纤维经不同温度热处理后的结构变化.研究结果表明,Fe-P合金对碳纤维的石墨化具有显著的催化效果.含Fe-P合金催化剂(P质量分数为7%)的聚丙烯腈基碳纤维经1 000℃热处理后,其石墨化度可达到71%,而不含Fe-P合金的空白样碳纤维经2 800℃热处理后石墨化度仅为30.1%,Fe-P合金催化剂大幅度降低了碳纤维的石墨化温度.同时,碳纤维的石墨化度随着Fe-P合金催化剂中P质量分数的增加而增大;随着Fe-P合金电沉积时间的延长而增大,直到镀层厚度达到一定值.本文还就Fe-P合金对碳纤维的催化石墨化机理进行了讨论,结果表明Fe-P合金对碳纤维的催化石墨化遵循溶解-析出机理.

Catalytic Graphitization of Carbon Fibers with Electrodeposited Fe-P Alloy Coating

The catalytic graphitization of carbon fibers with electrodeposited Fe-P alloy coating and the relationship between coating composition and graphitization temperature were studied.Carbon fibers with and without electrodeposited Fe-P coating were heat treated at different temperatures and the structural changes were characterized by X-ray diffraction,Raman spectroscopy and scanning electron microscope.The results have indicated that Fe-P alloy exhibits a significant catalytic effect on the graphitization of carbon fibers.The degree of graphitization of polyacrylonitrile(PAN)-based carbon fibers coated with Fe-P alloy(7% P) reaches 71% through heat treatment at 1 000 ℃.However,the degree of graphitization of carbon fibers without Fe-P alloy is only 30.1% after being heat treated at 2 800 ℃.The presence of Fe-P alloy catalyst greatly decreases the graphitization temperature of carbon fibers.Moreover,the degree of graphitization of the Fe-P alloy coated carbon fibers increases with the increase of P content in the Fe-P alloy.The degree of graphitization increases with the increase of the deposition time of Fe-P alloy,and remains unchanged until the thickness of the Fe-P alloy coating reaches a certain value.The mechanism of catalytic graphitization was also discussed and the results have shown that the effect of Fe-P alloy on carbon fibre catalytic graphitization follows the dissolve-precipitation mechanism.