The Field-Emission Performance of Carbon-Nanotube Composite Graphene

摘要

In this paper, we improved the field emission performance of carbon nanotube (CNT) material films as cathode by applying graphene to three different parameters of CNT composites. The field emission performance of CNTs has been significantly improved by applying graphene. In these three kinds of CNTs, the field emission performance of DWCNTs is the best, whose turn-on field and threshold electric field are low to 0.6 V/μm and 1.2 μm, respectively, and its current density is also high on 16 mA/cmn²n, The second one is the type I MWCNTs, which is short and thin, and its current density is about 4–8 mA/cmn²n. The worst effect belongs to the type II MWCNTs, because its current density is generally under 2 mA/cmn²n.