Spontaneous, catalyst-free formation of nitrogen-doped graphitic carbon nanocages

A simple approach for spontaneous, catalyst-free formation of highly graphitic nitrogen-containing carbon nanocages has been demonstrated by using commercially available graphite rods as the initial materials. The resultant carbon nanocages have well-ordered graphitic shells with more compact graphite layer structure than that of conventional bulk graphite. The incorporation of nitrogen into the graphitic backbone of carbon nanocages opens the potential for metal-free catalysis of oxygen reduction reaction in fuel cells. It is believed that the formation of carbon nanocages were attributed to the incurvature and coalescence of graphite sheets shelled off from graphite rods. Thermal gravimetric analysis revealed the as-prepared carbon nanocages possessed excellent thermal stability in both N2 (1200 °C) and air (700 °C) atmospheres promising for applications in high-temperature environments.