Superior field emission characteristics of highly crystalline and thermally stable carbon nanotubes grown in N2 and O2 by arc discharge

Multi-walled carbon nanotubes (MWCNTs) grown by chemical vapor deposition (CVD), which are commercially available in large quantities, commonly show poor field emission characteristics due to their low crystallinity. In this study, we fabricated highly crystalline MWCNTs using arc discharge (AD) via a mixture of N2 and O2 gases. The AD-MWCNTs showed a high oxidation temperature and lower threshold (Vth) and turn-on (Vto) voltages in repeated field emission measurements compared to CVD-MWCNTs. In a lifetime evaluation performed at an anode current of 3 mA for 20 and 120 h in diode and triode configurations, respectively, AD-MWCNTs showed better long-term stability than the CVD-MWCNTs. Thus, our findings demonstrate that AD-MWCNTs are promising for use in high-performance field emitters.