The invention provides a method for directionally constructing a micro-
nano porous structure between fibers of a fabric so as to enhance the
radiation cooling performance of the cotton fabric. In particular to a Janus knitted fabric with
radiation refrigeration and one-way
moisture conduction functions and a preparation method and application thereof, the front side of the Janus knitted fabric is hydrophilic cotton yarns, and the back side of the Janus knitted fabric is synthetic fibers; after weaving is completed, the reverse side of the Janus knitted fabric is coated with a
polymer solution containing inorganic micro-nano particles, and the distance gt of the synthetic fibers is regulated and controlled; the
diameter of the inorganic micro-nano particles and the spacing of the synthetic fibers are gt The
polymer solution is directionally distributed to the cotton
yarn layer due to the spacing of the hydrophilic cotton fibers, and then a micro-
nano porous structure is formed among the cotton fibers through non-
solvent induced phase separation. According to the Janus knitted fabric prepared by the invention, a micro-
nano porous structure is formed in situ between cotton fibers, the surface texture and macrostructure characteristics of the fabric are not influenced, the original hand feeling and hydrophilicity of the fabric are kept, and the Janus knitted fabric has an excellent
radiation cooling function.