Abstract:
Coal pitch, a byproduct of coal coking, is an ideal precursor for preparing conductive carbon fillers because of its rich aromatics and high yield of carbonization products. In this paper, coal pitch-based carbon materials with controllable morphology and structure were prepared by carbonization using coal pitch and multi-walled carbon nanotubes as raw material and structure-directing agent, respectively. The effect of carbon nanotubes on the structure and electrothermal properties of carbon materials was investigated. The results show that the doping of multi-walled carbon nanotubes results in an increase in the lattice arrangement order, a decrease in lattice spacing, and an increase in graphitization degree of conductive fillers, which leads to a significant increase in the carrier concentration of the carbon film and thus its conductivity. The doping of 2% carbon nanotubes can increase the carrier concentration of coal pitch-based carbon film by 3.2 times and reduce the resistance of coal pitch-based carbon film by 67%. At 5, 10 and 15 V, the heating temperature of the coal pitch-based carbon film can reach 44, 88 and 165 ℃, respectively, which is enhanced 7, 22 and 70 ℃ compared with the undoped carbon film, showing great application prospect.