Nitrogen-Doped Graphene and Its Application in Electrochemical Biosensing

TLDR

Chemical doping, especially nitrogen doping, modifies the electronic properties of carbon materials, and graphene’s two‑dimensional structure makes it attractive for bioelectronics and biosensing. This study presents a simple nitrogen‑plasma treatment of chemically synthesized graphene to produce N‑doped graphene and proposes a schematic of its structure. The method controls nitrogen incorporation by varying plasma exposure time, yielding N contents from 0.11 % to 1.35 % and defining the doped graphene’s structure. The resulting N‑doped graphene shows strong electrocatalytic activity for H₂O₂ reduction, rapid electron transfer with glucose oxidase, and enables glucose detection down to 0.01 mM amid interferences.

Abstract

Chemical doping with foreign atoms is an effective method to intrinsically modify the properties of host materials. Among them, nitrogen doping plays a critical role in regulating the electronic properties of carbon materials. Recently, graphene, as a true two-dimensional carbon material, has shown fascinating applications in bioelectronics and biosensors. In this paper, we report a facile strategy to prepare N-doped graphene by using nitrogen plasma treatment of graphene synthesized via a chemical method. Meanwhile, a possible schematic diagram has been proposed to detail the structure of N-doped graphene. By controlling the exposure time, the N percentage in host graphene can be regulated, ranging from 0.11 to 1.35%. Moreover, the as-prepared N-doped graphene has displayed high electrocatalytic activity for reduction of hydrogen peroxide and fast direct electron transfer kinetics for glucose oxidase. The N-doped graphene has further been used for glucose biosensing with concentrations as low as 0.01 mM in the presence of interferences.