▎ 摘　　要

NOVELTY - Preparing nickel sulfide/reduced graphene oxide (NiS/rGO) composite material involves compounding graphene oxide (GO) and nickel sulfide (NiS) nanowire, and obtaining NiS/GO composite material, then performing heat treatment to prepare NiS/rGO composites. USE - Method for preparing NiS/rGO composite material used as a gas sensing material, and for nitrogen oxide gas detection method for nitrogen oxide gas sensor (all claimed). ADVANTAGE - The composite material formed by reduced graphene oxide and metal sulfide exhibits semiconductor properties as a whole, and electrons are captured to reduce the electron concentration in the material, and hole concentration increases, which is the hole conduction type, so the conductivity of the sensor increases and the resistance decreases. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a nitrogen oxide gas detection method, which involves placing NiS/rGO composite gas sensor in an environment containing nitrogen oxide gas to complete nitrogen oxide gas detection.