Simultaneous Synthesis and Nitrogen Doping of Free-Standing Graphene Applying Microwave Plasma

Abstract

An experimental and theoretical investigation on microwave plasma-based synthesis of free-standing N-graphene, i.e., nitrogen-doped graphene, was further extended using ethanol and nitrogen gas as precursors. The in situ assembly of N-graphene is a single-step method, based on the introduction of N-containing precursor together with carbon precursor in the reactive microwave plasma environment at atmospheric pressure conditions. A previously developed theoretical model was updated to account for the new reactor geometry and the nitrogen precursor employed. The theoretical predictions of the model are in good agreement with all experimental data and assist in deeper understanding of the complicated physical and chemical process in microwave plasma. Optical Emission Spectroscopy was used to detect the emission of plasma-generated ‘‘building units’’ and to determine the gas temperature. The outlet gas was analyzed by Fourier-Transform Infrared Spectroscopy to detect the generated gaseous by-products. The synthesized N-graphene was characterized by Scanning Electron Microscopy, Raman, and X-ray photoelectron spectroscopies.

On the transition of reaction pathway during microwave plasma gas‐phase synthesis of graphene nanosheets: From amorphous to highly crystalline structure

“…Such balance can be significantly altered by the presence of a reactive gas (e.g., O 2 or H 2 ), as it affects both plasma parameters [ 50 ] and chemical composition. [ 51 ] This can be either unintentional (impurities) or intentional (deliberate admixture). Reactions of admixtures with HC fragments (CH x and C 2 H y ) formed during the ethanol decomposition lead to alternative reaction pathways not originally present in the process and, as a consequence, directly influence the process of nucleation and growth of GNS.…”

Cryptand-Functionalized Highly Oriented Pyrolytic Graphite Electrodes

“…The X-ray Photoelectron Spectroscopy (XPS) study was performed using an XSAM800 non-monochromatic spectrometer from KRATOS. Operating conditions, spectra acquisition and data treatment were as described elsewhere [34]. The charge shift was corrected using the binding energy of 284.8 eV as reference.…”

Advances in Microwave‐Enhanced Chemical Vapor Deposition for Graphene Synthesis

“…As the concentration of N 2 increased, the I D /I G ratio increased from 0.6 to 2 and I 2D /I G ratio decreased from 1.5 to 0.7 which indicated more disordered structure was formed. Tsyganov et al [34] prepared free-standing N-graphene using ethanol as carbon source and N 2 as nitrogen precursors by a single-step method at atmospheric pressure. Ar (1320 sccm), ethanol (30 sccm) and N 2 (30 sccm) were introduced into for depositing N-graphene at 2 kW microwave power.…”