▎ 摘　　要

NOVELTY - Preparing biomass carbon-based composite film using strip-shaped graphene oxide as binder comprises e.g. (i) carbonizing one-dimensional tubular biomass and calcining at 500-1000 degrees C to obtain biomass carbon precursor, mixing biomass carbon precursor and potassium hydroxide, uniformly activating and calcining to obtain sample A, mixing sample A and mixed solution B to obtain sample C, hydrothermally oxidizing sample C, cooling, filtering, washing with deionized water until neutral, drying to obtain biomass carbon tube, (ii) preparing graphene oxide dispersion liquid using Hummers method, sonicating, quickly spraying the graphene oxide dispersion liquid into the receiving device filled with liquid nitrogen, volatilizing, freezing overnight and melting to obtain strip-shaped graphene oxide, and (iii) mixing biomass carbon tube material and strip-shaped graphene oxide dispersion liquid, performing ultrasonic treatment, vacuum filtering, dry peeling and performing reduction treatment. USE - The biomass carbon-based composite film is useful in flexible supercapacitor electrode materials (claimed). ADVANTAGE - The composite film: utilizes one-dimensional tubular fibers to hinder graphene agglomeration; and improves the electrochemical performance of flexible supercapacitors. DETAILED DESCRIPTION - Preparing biomass carbon-based composite film using strip-shaped graphene oxide as binder, comprises (i) carbonizing one-dimensional tubular biomass and calcining at 500-1000 degrees C to obtain biomass carbon precursor, and mixing biomass carbon precursor and potassium hydroxide in mass ratio of 1-3:1-4 and then uniformly activating and calcining at 700-1000 degrees C to obtain sample A, mixing sample A and mixed solution B in a material-liquid ratio of 0.2-2 mg.ml-1 to obtain sample C, hydrothermally oxidizing sample C at 70-200 degrees C, cooling to room temperature, filtering, washing with deionized water until neutral, drying at 70-100 degrees C for 10-14 hours to obtain biomass carbon tube, where the mixed solution B includes deionized water and nitric acid with mass fraction of 68% in a volume ratio of 1-10:1-2, (ii) preparing the graphene oxide dispersion liquid to be 0.2-1.5 mg.ml-1 using Hummers method, sonicating at 600 W for 30 minutes to make it evenly dispersed, quickly spraying the graphene oxide dispersion liquid into the receiving device filled with liquid nitrogen, then completely volatilizing, freezing overnight, and melting at room temperature to obtain strip-shaped graphene oxide, and (iii) mixing biomass carbon tube material and strip-shaped graphene oxide dispersion liquid in a mass ratio of 1-12:1, and subjecting to 600W ultrasonic treatment for 1 hours, vacuum filtering, dry peeling, and performing reduction treatment to obtain biomass carbon-based composite film material.