▎ 摘　　要

NOVELTY - Preparation of graphene-based heat and moisture exchange composite film involves (i) subjecting a natural flake graphite ethanol slurry or an expandable graphite ethanol slurry to a surfactant modification treatment by a condensation reflux method, (ii) ultrasonically treating the prepared slurry by supercritical carbon dioxide fluid method at 35-45 degrees C and pressure of 20-30 MPa for 20-26 hours and centrifuging the supernatant to obtain graphene quantum dots having particle size of 10-75 nm, (iii) immersing the microporous polyester film in the graphene quantum dot slurry, (iv) introducing the metal-organic framework precursor synthesis solution to the graphene quantum dot slurry, and depositing graphene quantum dots and metal organic framework in situ on the polyester microporous membrane after 24 hours, and (v) drying the polyester microporous membrane using 80-120 W microwave dryer for 10-20 minutes. USE - Preparation of graphene-based heat and moisture exchange composite film used as core material of membrane type heat exchange system. ADVANTAGE - The method produces composite film having excellent heat and moisture transmission properties, mechanical properties, and chemical stability. The heat exchange system has actively developed as an energy saving and environmentally protective device which effectively improves indoor air quality and reduces air-conditioning energy consumption.