▎ 摘　　要

NOVELTY - Vertically-oriented graphene/nano-fiber composite film material comprises graphene having vertically-oriented channels arranged in an array, and nanofibers that shuttle between graphene and channels. USE - Vertically-oriented graphene/nano-fiber composite film material used in distillation medium of distillation device. ADVANTAGE - The vertically-oriented graphene/nano-fiber composite film material has excellent mechanical property, is easily compressed, bent and stretched, and structure is not damaged, and maintains high distilling efficiency. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) method for preparing a vertically-oriented graphene/nano-fiber composite film material, which involves mixing graphene oxide dispersion liquid and nanofiber dispersion liquid to obtain mixed liquid; placing the mixed liquid in a predetermined container, and contacting the bottom of the predetermined container with a cold source to perform orientation freezing from bottom to top to obtain a vertically oriented graphene oxide/nano fiber composite membrane material; freeze-drying the vertically oriented graphene oxide/nanofiber composite film material; and performing reduction treatment is performed on the vertically-oriented graphene oxide/nano-fiber composite film material after the freeze-drying to obtain vertically-oriented graphene/nano-fiber composite film material; (2) distillation medium comprises vertically-oriented graphene/nanofiber composite membrane material; and (3) distillation device comprises the distillation medium, where the distillation medium is disposed on a surface of a liquid to be distilled.