▎ 摘　　要

NOVELTY - Graphene/metal organic framework composite structure prepared by (i) using chemical vapor deposition method at high temperature, using methane and hydrogen as gas sources for growing single-layer graphene on copper foil, (ii) transferring the single-layer graphene on the copper foil to the substrate, and(iii) using hydrothermal method or vapor phase growth method, using single-layer graphene as template, epitaxially growing metal organic framework on its surface to obtain graphene/metal organic framework composite structure. USE - Used as graphene/metal organic framework composite structure. ADVANTAGE - The structure: has high sensitivity, and wide linear range of detection signals; and achieves other selective identification. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for use of graphene/metal organic framework composite structure, comprising (i) assembling metal-organic frame/graphene composite structure resistance devices, using two methods for assembling metal-organic frame/graphene composite structure resistance devices, assembling metal-organic frame/graphene composite structure resistor device array by photolithography or mask printing methods, where the array uses conductive metal as the electrode material, and channel size of the device is about 1-10 microns, directly fabricating indium electrodes on both ends of the film of the metal organic frame/graphene composite structure to obtain millimeter or centimeter-sized resistor devices, (ii) establishing the specific response curve of the metal-organic framework/graphene composite structure to different gas molecules, the recognition and detection of different gas molecules can be realized, where the resistance device of the above composite structure has different gas molecules and different concentrations, resistance value will change accordingly under specific voltage, collecting current data points regularly, measuring the resistance of the device, and obtaining series of discrete data, and then using the first-order reaction kinetic formula for fitting to obtain specific response curves of the metal-organic framework/graphene composite structure to different gas molecules, where the response curve reflects the gas concentration and reaction rate, and the mathematical relationship between the response value and the gas concentration, and realizing the specific recognition of gas molecules. The method comprises using the first-order reaction kinetic formula for fitting the response curve of different gas molecules at different concentrations, responding of ammonia molecules, when the response reaches equilibrium, response value and the concentration of gas molecules conform to the Langmiur-Freundlich chemical adsorption model, fitting the response curve at the initial stage of response at low concentration, and further exploring the linear correlation between the reaction rate and the concentration of gas molecules. The method comprises using a Kelvin probe force microscope for testing the potential difference between the metal organic frame structure and graphene, and assembling graphene film field effect transistor devices, and deriving the electron transfer mechanism between the metal organic framework and graphene, using Raman spectroscopy for characterizing the shift of the graphene 2D peak before and after the adsorption of gas molecules, revealing the electron transfer mechanism when gas molecules are adsorbed on the surface of the metal organic framework/graphene structure.