The effect of varying N/C ratios of nitrogen precursors during non-metal graphene catalyst synthesis

By Soo, Li Ting; Loh, Kee Shyuan; Mohamad, Abu Bakar; Daud, Wan Ramli Wan
Published in International Journal of Hydrogen Energy NULL 2016

Abstract

Abstract Nitrogen-doped carbon materials have great potential as metal-free catalysts in a variety of applications, including batteries, supercapacitors and fuel cells. In this paper, nitrogen-doped graphene (NG) catalysts were synthesized via thermal annealing with varying ratios of graphite oxide and melamine precursors. The {NG} catalysts were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The prepared {NG} catalysts were folded transparent films with wrinkles. The nitrogen content of the {NG} catalysts calculated from {XPS} varied from approximately 4.18%-7.40%. {NG1} displayed the highest performance, with a remarkable reduction peak of 0.39 mA cm?2 at ?0.21 V vs. Ag/AgCl in alkaline media. A direct correlation between total nitrogen content and catalytic activity was not observed, but catalytic activity was dependent on the nature of the nitrogen configurations. {XPS} analysis revealed that the high catalytic activity of {NG1} is attributable to the configuration of the graphitic N-type nitrogen.

Read » Back