▎ 摘　　要

NOVELTY - High thermal conductivity and water transmission composite film material, comprises graphene and cellulose nanofibers. USE - The high thermal conductivity and water transmission composite film material is useful in a solar evaporator (claimed). ADVANTAGE - The composite film material: has rich hydrophilic nano-pores and dense graphene sheet layer accumulation; achieves fast water transfer and high thermal conductivity; and quickly transfers the heat generated by the photothermal conversion to the water nanofluid between the graphene layers, and accelerates the evaporation of water. When the composite film material is used as a solar evaporator: the evaporation rate can reach 1.47 kg/m2/hour under 1 times the intensity of sunlight; evaporation rate 4.51 kg/m2/hour under 3 times the sunlight intensity; and maintains 95% evaporation efficiency. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing high thermal conductivity and water transmission composite film material, comprising (i) configuring the graphene and the cellulose nanofiber into a mixed solution, (ii) ultrasonically dispersing the mixed solution in the ultrasonic cleaner, then stirring by magnetic stirrer, repeating the ultrasonic dispersion and the stirring process to obtain uniform graphene-nano cellulose fiber dispersing solution, and (iii) performing suction filtration of the graphene-nanocellulose fiber dispersion solution into a film, and drying to obtain final product.