▎ 摘　　要

NOVELTY - Graphene oxide fiber comprises graphene oxide sheets (4) and an additive. The graphene oxide sheets are stacked layer by layer and curled in the same direction to form a strip-shaped structure (3), and the additive is positioned between the graphene oxide sheets. The additive is bound to the surface of the graphene oxide sheets or adsorbed between graphene oxide sheet layers by an electric charge. Each layer of graphene oxide is in a closed cylindrical shape, and the graphene oxide on the outer layer surrounds the graphene oxide on the inner layer. The graphene oxide fibers have a radial dimension of 1-10 mu m, and a length of 10 to 100 mu m. The additive comprises one or a combination of two or more of a soluble potassium salt, a soluble calcium salt or ethylenediamine. USE - The graphene oxide fiber is useful for preparing composite slurry of graphene oxide fibers and graphene oxide sheets, graphene oxide fiber cloth, and graphene gas diffusion membrane (all claimed). ADVANTAGE - The graphene gas diffusion membrane is good in electrical conductivity and thermal conductivity and has good air permeability and water permeability. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) preparing graphene oxide fiber which involves uniformly mixing the solution dispersed with the additive and the graphene oxide dispersion liquid to obtain graphene oxide slurry; and spinning the graphene oxide slurry to obtain the graphene oxide fiber; (2) a composite slurry of graphene oxide fibers and graphene oxide sheets, comprising the graphene oxide fibers, graphene oxide sheets, and a solvent; the solvent comprises water or NMP; the content of the graphene oxide fiber is 3-10%; the mass ratio of the graphene oxide sheets to the solvent is (0.5-1):(99-99.5); and the graphene oxide sheets have less than or equal to 3 layers; (3) preparing composite slurry of graphene oxide fibers and graphene oxide sheets, which involves preparing graphene oxide fibers using the method above; dispersing graphene oxide sheets in a solvent to obtain a graphene oxide dispersion liquid; and dispersing graphene oxide fibers into a graphene oxide dispersion liquid to form a composite slurry of graphene oxide fibers and graphene oxide sheets; the solid content of graphene oxide sheets in the graphene oxide dispersion liquid is 0.5-1%; (4) a graphene oxide fiber cloth comprising the graphene oxide fiber and graphene oxide sheets, where the graphene oxide sheets are wound around the graphene oxide fiber in a crimped manner, the graphene oxide fibers are connected, and the connected graphene oxide fibers are interwoven into a net shape; preferably, the graphene oxide sheets have less than or equal to 3 layers; (5) preparing graphene oxide fiber cloth which involves preparing a composite slurry of graphene oxide fibers and graphene oxide sheets using the method above; depositing the composite slurry on a mesh fabric, drying, and stripping the mesh fabric to obtain graphene oxide fiber cloth; preferably, the mesh number of the mesh cloth is 200-1000 meshes; (6) graphene gas diffusion membrane characterized by being formed by interweaving strip-shaped graphene, where intersection points of the interweaved strip-shaped graphene are wound by curled flaky graphene; the graphene gas diffusion membrane has a porosity of 65-80%; the graphene gas diffusion membrane has a conductivity of (2-5)x 105 S/m; and the thermal conductivity of the graphene gas diffusion film is 300-600 W/m.K; and (7) preparing graphene gas diffusion membrane which involves preparing a graphene oxide fiber cloth by the method above; and reducing the graphene oxide fiber cloth to obtain the graphene gas diffusion membrane. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic structural view of of intersection points of strip-shaped graphene of the graphene gas diffusion membrane. Graphene strip (3) Graphene oxide sheet (4)