Facile synthesis of 3D sulfur/nitrogen co-doped graphene derived from graphene oxide hydrogel and the simultaneous determination of hydroquinone and catechol

Herein, a three-dimensional self-assembled hydrogel of graphene oxide sheets induced by pyrrole and Co2+ is described. Controlled shrinkage and sulfur/nitrogen co-doping occurred in the subsequent hydrothermal process. The obtained 3D sulfur/nitrogen co-doped graphene was further dried through direct evaporation, without freeze-drying. SEM images demonstrated a surface 3D structure with high roughness and composed of interconnected sheets. This newly fabricated 3D sulfur/nitrogen co-doped graphene was used in the simultaneous detection of catechol and hydroquinone with low detection limits of 0.28 and 0.15 μM, respectively.