▎ 摘　　要

NOVELTY - Composite structure nano-enzyme comprises a substrate and a metal oxide nano-array grown on the surface of the substrate, where the substrate is a two-dimensional layered nano-material, and the mass ratio of the two-dimensional layered nano-material to the metal oxide nano-array is (1-5):(1-4). USE - Composite structure nano-enzyme is used in nano-enzyme electrochemical sensor, which is used for detecting nitrobenzene compound, where the detecting object is 2,4,6-tri-nitrotoluene, 2,4-dinitrotoluene, p-nitrotoluene, parathion, methylparathion or pentachloronitrobenzene (all claimed). ADVANTAGE - The sensor has high detection sensitivity, good selectivity, simple operation, and short response time. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a method for preparing nano-enzyme with composite structure, which involves dispersing the two-dimensional layered nano-material in de-ionized water, absolute ethyl alcohol or dimethylformamide solution, coating the obtained dispersion on the surface of the silicon sheet, drying, dissolving the metal salt precursor in absolute ethyl alcohol or de-ionized water, coating on the silicon sheet, drying, calcining, taking out after cooling, preparing mixed aqueous solution containing metal salt, precipitating agent and surfactant, placing the cooled silicon sheet above the mixed aqueous solution to react, taking out after finishing reaction, washing; drying, calcining, obtaining the composite structure nano-enzyme; (2) a nano-enzyme electrochemical sensor, which comprises an electrochemical sensing chip working electrode deposited with the composite structure nano-enzyme; and (3) a method for preparing nano-enzyme electrochemical sensor, which involves dispersing the composite structure nano-enzyme in the mixed solution prepared by absolute ethyl alcohol and Nafion (RTM: Sulfonated tetrafluoroethylene based fluoropolymer-copolymer) solution in (3-8):1 ratio to obtain the 10-50 mg/mL composite structure nano enzyme, ultrasonically processing for 15-45 minutes to obtain the ink, depositing the ink on the surface of the electrochemical sensing chip working electrode, drying at room temperature to obtain the nano-enzyme electrochemical sensor.