▎ 摘　　要

NOVELTY - Preparation of composite material involves dispersing graphene oxide in water, adding thiourea, stirring, heat preserving, naturally cooling, washing with deionized water and ethanol, drying, heating to obtain three-dimensional nitrogen and sulfur doped graphene, dissolving carboxylated beta -cyclodextrin in phosphate-buffered saline (PBS) solution to obtain carboxylated beta -cyclodextrin solution, adding 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS) and stirring to obtain activated carboxylated beta -cyclodextrin solution, dripping chitosan solution into activated carboxylated beta -cyclodextrin solution, stirring, washing with acetic acid and deionized water, freeze-drying to obtain chitosan beta -cyclodextrin powder, adding chitosan beta -cyclodextrin powder to deionized water, ultrasonically stirring, adding three-dimensional nitrogen and sulfur doped graphene, ultrasonically processing, stirring, centrifuging and washing with deionized water to composite. USE - Preparation of composite material used in electrochemical sensor (all claimed), super capacitors, lithium ion batteries and nano-materials. ADVANTAGE - The prepared composite material has improved electron transmission performance. DETAILED DESCRIPTION - Preparation of composite material involves dispersing 150-155 mg graphene oxide in 30-35 mL water, adding 450-455 mg thiourea, stirring for 4-5 hours, heat preserving at 175-185 degrees C for 12-13 hours, naturally cooling to room temperature, washing with deionized water and ethanol, drying under vacuum at room temperature, heating to 700-710 degrees C at rate of 3-5 degrees C/minute in argon atmosphere for 1-1.5 hours for reduction to obtain three-dimensional nitrogen and sulfur doped graphene, dissolving carboxylated beta -cyclodextrin in 50-55 mL of 0.1 M phosphate-buffered saline (PBS) solution having pH of 7.0 to obtain carboxylated beta -cyclodextrin solution having mass and volume concentration of 2 mg/mL, adding 50-55 mg 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 50-55 mg N-hydroxysuccinimide (NHS) and stirring to obtain activated carboxylated beta -cyclodextrin solution, dissolving chitosan in 50-55 mL of 0.1 M acetic acid solution to obtain chitosan solution having concentration of 2.1 mg/mL, slowly dripping chitosan solution into the activated carboxylated beta -cyclodextrin solution, stirring for 4-4.5 hours, washing with 0.1 M acetic acid and deionized water to obtain product, freeze-drying at -50 to -52 degrees C for 24-25 hours to obtain chitosan beta -cyclodextrin powder, adding chitosan beta -cyclodextrin powder to deionized water, ultrasonically stirring to obtain homogeneous solution, then adding three-dimensional nitrogen and sulfur doped graphene, ultrasonically processing, stirring, centrifuging and washing with deionized water to obtain three-dimensional nitrogen-sulfur doped graphene/self-assembled polysaccharide composite. An INDEPENDENT CLAIM is included for application method of composite material, which involves uniformly dispersing the composite material into water to form dispersion having concentration of 1-1.2 mg/mL, applying dispersion drop on the surface of the treated glassy carbon electrode to form modified electrodes, immersing in supporting electrolyte comprising 0.1 M potassium chloride and 5 mM ferricyanide (Fe(CN)6)4-/3- and measuring electrochemical performance by performing cyclic voltammetry with scanning potential of -0.2 to 0.6 V.