Guanidine, amitrole and imidazole as nitrogen dopants for the synthesis of N-graphenes

Abstract

Three N-containing organic compounds – guanidine, amitrole (3-amino-1,2,4-triazole) and imidazole were selected and evaluated as new nitrogen dopants for the preparation of N-graphene. A graphene oxide aqueous dispersion was subjected to hydrothermal treatment at 180 °C for 8 h in the presence of the selected N-compounds. The nitrogen contents in the resultant N-graphenes were as high as 13.4 at%, which is among the highest reported for graphene materials. The X-ray photoelectron spectroscopy revealed that pyridinic nitrogen was predominant in all of the N-graphenes, accounting for up to 47% of the total nitrogen content. Deoxygenation of graphene oxide under hydrothermal conditions was also improved through the use of the N-compounds. Possible reaction mechanisms between graphene oxide and each N-compound are proposed.