▎ 摘　　要

Graphene, a single sheet of graphite, in situ doping was performed using nitrogen sources like ammonia and pyridine. Based on the conducted experiments, nitrogen doped graphene was successfully synthesized and this was confirmed by the Raman spectroscopy and EDS analysis. Nitrogen doping of the graphene layer was found to be much more successful in terms of nitrogen content and homogeneity when only pyridine was utilized in comparison to the doping only with ammonia. The pyridine was used both as carbon and nitrogen source. However, nitrogen-doped single layer graphene was only achieved using pyridine along with a small amount of methane. It was found that the sheet resistance of the graphene film decreased with the doping in comparison to the pristine graphene. Reducing the sheet resistance is a quiet important development for the graphene to be employed in the optoelectronic devices particularly in solar cells. (C) 2019 Elsevier B.V. All rights reserved.