A simple, novel approach is proposed for the preparation of plasma-exfoliated graphene (PEGN) by reducing graphene oxide (GO) through a dielectric-barrier discharge (DBD) plasma treatment in a H2 atmosphere. The surface chemistry, microstructures, and crystallinity of the prepared samples were characterized via X-ray photoelectron spectroscopy, transmission electron microscopy, and Raman spectrometry to determine the formation mechanism of the PEGN. The results demonstrated that the prepared PEGN had only a few layers in its structure and that most of the functional groups containing oxygen on the GO surface were removed. The PEGN exhibited a considerably higher capacity, better cycling stability, and favorable electron transfer rate for use as a cathode material for lithium-ion batteries. This proposed approach is fast, convenient, and inexpensive, constituting a novel means of producing graphene.

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Carbon black was prepared by pyrolysis of propane under different plasma conditions. The effects of the flow ratio of the carbon precursor, discharge current, and plasma gases (including argon, nitrogen, and hydrogen) on the morphology and structure of carbon black were investigated by a series of physical characterizations. The equilibrium components were computed based on the minimization of the Gibbs free energy. The theoretical analysis and experimental results confirmed that HCN is the inevitable byproduct in the tail gas from the nitrogen plasma process, indicating that nitrogen is inappropriate as the carrier gas for the preparation of carbon black. The effects of discharging current, discharging spacing, and proportions of propane were also symmetrically studied by the evaluation of HCN concentration. Moreover, the graphene was generated when using argon as the plasma gas mixed with a small amount of hydrogen.