Effects of ammonia plasma treatment on the surface characteristics of carbon fibers

Carbon fibers were grown from cobalt catalysts with larger size (> 100 nm), and the size distribution can be controlled by pretreatment. Pretreated cobalt catalytic-layers were observed as islands, which can enhance the growth of carbon fibers. The carbon fibers were treated by ammonia plasma in a PECVD system. High-energy ammonia plasma not only can cause damage but also adsorb on carbon fibers. The ammonia plasma treatment resulted in the etching effect. It is also observed that the more treatment time, the more disorder in structures of carbon fibers. The N–H functional groups were found on the surfaces of ammonia plasma treated carbon fibers and this observation can be further investigated to develop chemical sensor application.