Two-Step Approach to Obtain Nitrogen-Doped Reduced Graphene Oxide Using Nitrogen-Containing Reducing Agents.

N-doping of graphene has emerged as a very valuable alternative for diverse applications. Nonetheless, further work is required to explore the grafting of N-containing molecules onto graphene to incorporate N atoms into its graphitic network, thereby harnessing a wide variety of available N-containing molecules. Here, the chemical reduction of graphene oxide (GO), using nitrogen-containing reducing agents such as ethylenediamine (EDA) and dimethylformamide (DMF), was explored to evaluate their effect on the surface composition of the obtained reduced graphene oxides (rGO). Afterward, an 800 °C thermal treatment was performed, and the samples were characterized before and after the thermal treatment, focusing on the nitrogen and oxygen functional groups present on the rGO. Several fingerprints were identified from the grafting of the EDA molecules functionalizing the rGO-EDA sample by XPS, FTIR, and UV-visible spectroscopy measurements and by first-principles calculations. The 800 °C thermal treatment led to significant changes in the surface chemistry, incorporating nitrogen as a dopant into the rGO to imprint the obtained N-rGO sample with electrocatalytic properties (Oxygen Reduction Reaction activity). Therefore, the proposed approach opens the possibility to explore a myriad of N-containing molecules for N-doping of rGO.