▎ 摘　　要

NOVELTY - A three-dimensional nitrogen-doped graphene composite material preparing method involves obtaining substrate-containing three-dimensional nitrogen-doped graphene by taking a foam material as a substrate and using a chemical vapor deposition technique in the presence of inert gas, hydrogen, a carbon source and a nitrogen source, and obtaining the three-dimensional nitrogen-doped graphene composite material by etching and cleaning the three-dimensional nitrogen-doped graphene. USE - Method for preparing three-dimensional nitrogen-doped graphene composite material that is utilized in electrochemical biosensors field (claimed). ADVANTAGE - The method enables preparing the graphene composite material with high specific surface area, good biocompatibility and high conductivity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for the following: (1) a three-dimensional nitrogen-doped graphene composite material (2) a method for utilizing a three-dimensional nitrogen-doped graphene composite material in electrochemical biosensors field.