▎ 摘　　要

NOVELTY - Preparing modified graphdiyne nano-sheet, comprises calcining the graphene nano-sheet at 200-1000degrees Celsius for 1-5 hours at a heating rate of 1-10degrees Celsius/minute under an inert atmosphere to obtain the modified graphene nano-sheet. USE - The modified graphdiyne nano-sheet and sensor element is useful as a gas sensing material for room temperature nitrogen dioxide sensor element or in preparing room temperature nitrogen dioxide sensor element and in environmental monitoring, non-invasive pulmonary function monitoring, safety detection of toxic, harmful, flammable and explosive gases in the petrochemical field (all claimed). ADVANTAGE - The method can change the functional groups and defects on the surface of the graphite alkyne nano-sheet material, changing the electronic property of the material, and significantly improving the gas-sensitive property of material. The room temperature nitrogen dioxide sensor has excellent performance on nitrogen dioxide at room temperature, with a response value of 6% at 250 ppb, which can realize the ppb-level high-sensitivity detection at room-temperature. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: modified graphdiyne nano-sheet; room temperature nitrogen dioxide sensor element; preparation method of the room temperature nitrogen dioxide sensor element; and room temperature nitrogen dioxide sensor.