▎ 摘　　要

NOVELTY - A method for constructing graphite-phase carbon nitride quantum dot/carbon composite material, involves (1) using nitrogen-rich material as a precursor to calcine, taking out and grinding to obtain graphite-phase carbon nitride powder, (2) putting the graphite-phase carbon nitride powder into a centrifuge tube, slowly adding liquid nitrogen to it, and then putting the centrifuge tube into a Dewar flask filled with liquid nitrogen, (3) adding the graphite-phase carbon nitride powder into the dispersant, (4) centrifuging the mixture peeled off in step (3) in a centrifuge, using a dialysis bag to remove the solvent, and freeze-drying the dialyzed liquid to obtain graphite-phase carbon nitride quantum dots, (5) adding the graphite-phase carbon nitride quantum dots and carbon materials into distilled water, (6) centrifuging the solid-liquid mixture obtained in step (5) and obtaining graphite-phase carbon nitride quantum dots/carbon composite material, and drying. USE - Method for constructing graphite-phase carbon nitride quantum dot/carbon composite material based on non-covalent bonding used in dye-sensitized solar cells (claimed). ADVANTAGE - The composite material integrates excellent catalytic performance of graphite-phase carbon nitride quantum dot and good conductive performance of carbon material, and exhibits excellent performance for electrode I3-reduction. The method has simple preparation technique, mild condition, low energy consumption, high efficiency, and low cost. DETAILED DESCRIPTION - A method for constructing graphite-phase carbon nitride (g-C3N4) quantum dot/carbon composite material based on non-covalent bonding, involves (1) using a high-temperature thermal polymerization method, and using 6-10 g nitrogen-rich material as a precursor to calcine at a high temperature of 450-600degrees Celsius in air or nitrogen atmosphere for 2-4 hours, taking out and grinding to obtain graphite-phase carbon nitride powder, and selecting the nitrogen-rich material from one of melamine, urea or dicyandiamide, (2) putting the graphite-phase carbon nitride powder obtained in step (1) into a centrifuge tube, slowly adding liquid nitrogen to it, and then putting the centrifuge tube into a Dewar flask filled with liquid nitrogen, adding foam cover and pre-treating at low temperature for 10-90 minutes, (3) adding the graphite-phase carbon nitride powder processed in step (2) into the dispersant for liquid phase stripping for 1-5 hours, maintaining the ratio of the mass of the graphite-phase carbon nitride powder to the volume of the dispersant to be 1-4 mg/mL, (4) centrifuging the mixture peeled off in step (3) in a centrifuge with a rotational speed of 6000-12000 rpm for 5-15 minutes, and collecting the centrifuged upper layer liquid, using a dialysis bag with a molecular weight cut-off of 200 to dialysis for 3-5 days to remove the solvent, and freeze-drying the dialyzed liquid to obtain graphite-phase carbon nitride quantum dots, (5) adding the graphite-phase carbon nitride quantum dots and carbon materials obtained in step (4) into distilled water and stirring magnetically for 2-5 hours, and coupling the two materials through a non-covalent stacking effect, maintaining the mass ratio of graphite-phase carbon nitride, carbon material and distilled water to be 1:10-50:10-50, (6) centrifuging the solid-liquid mixture obtained in step (5) in a centrifuge with a rotational speed of 8000-20000 rpm for 5-15 minutes, collecting the lower layer material, and obtaining graphite-phase carbon nitride quantum dots/carbon composite material after freeze-drying, modifying the graphite-phase carbon nitride quantum dots in the graphite-phase carbon nitride quantum dots/carbon composite material on the surface of the carbon material by the non-covalent bond stacking effect. The dispersant used in the liquid phase stripping is selected from one or two of ethanol, isopropanol, acetone, dimethylformamide or water. The carbon material is selected from one of carboxylated multi-walled carbon nanotubes, carboxylated single-walled carbon nanotubes, carbon nanobelts or graphene. The elements contained in the graphite-phase carbon nitride quantum dot/carbon composite material are carbon, nitrogen and oxygen, and the atomic percentage of nitrogen is 2-13%.