Synthesis of high crystalline carbon-nitrogen layered compounds by CVD using nickel and cobalt catalysts

Abstract

Carbon-nitrogen layered compounds, C x Ns, have been synthesized by thermal decomposition (CVD) of acetonitrile and pyridine with nickel or cobalt catalyst at 800–1200 °C. Acetonitrile yielded C 14NC 62N at 800–1100 °C and pyridine gave C 25NC 60N containing less nitrogens at 800–1000 °C. The nitrogen concentrations were the highest in the products, C 14NC 16N prepared from acetonitrile in the temperature range, 850–1000 °C. X-ray diffraction patterns indicate that the C x N samples have the same layered structures as usual carbon materials. The use of nickel or cobalt catalyst highly improves the crystallinity of C x N samples, and increases the nitrogen atoms incorporated in graphene layers compared with the pyridine type nitrogens existing at the edge of graphene layers. No distinct difference was found in the compositions and crystallinity of C x Ns prepared with two kinds of catalysts, nickel and cobalt.