A Structural Evaluation of Fir Powder in the Graphitization Process with Iron Oxide at a Low Temperature

Abstract

Catalytic graphitization of fir powder with iron oxide was investigated to fabricate high crystalline carbon between 900°C and 1600°C under nitrogen atmosphere. The effects of the catalyst concentration and the heat treatment temperature on the graphitization process of fir carbon were investigated, and the structural evaluation in the graphitization process was analyzed by X-ray diffraction (XRD), high-resolution transmission microscopy (HRTEM), and laser Raman (LR). XRD analysis shows that the rate of graphitization increased with increasing iron concentration and heat treatment temperature, and the turbostratic and graphitic carbon were formed due to the different catalytic graphitization mechanism of iron and iron carbide at different heat treatment temperatures. HRTEM images indicate that the graphitic carbon materials possessed a high crystallinity with coil morphology. LR analysis shows that the I_D/I_G value decreased from 1.61 to 0.37 with increasing temperature and from 1.4 to 0.37 with increasing iron concentration. The key factor to affect graphitization behavior of fir powder was the thermal treatment temperature compared with the catalyst concentration.

Keywords:

• Catalytic graphitization
• fir powder
• iron oxide
• structural evaluation
• mechanism

Acknowledgment

The authors gratefully acknowledge the support of the National Natural Science Foundation of China (NSFC) (Grant No. 50773017, 50973024).