▎ 摘 要
Graphene is a promising material for membrane applications. However, the graphene production with large specific area and good structural quality is a challenge. Therefore, the production and characterization of composite membranes with graphene grown by chemical vapor deposition (CVD) over a porous polymethylmethacrylate (PMMA) substrate was investigated. The experimental strategy consisted in applying CVD-graphene on a PMMA surface using PMMA-assisted graphene wet transfer. The proposed methodology resulted in large-area membranes with 2 cm diameter. The samples were characterized by Raman spectroscopy, indicating the presence of graphene in good quality and relative structural integrity. The analysis by scanning electron microscopy revealed the formation of a microporous support with an asymmetric structure. The gas permeation measurements of graphene/PMMA membranes showed a permeability reduction of 81.9% for CO2 and 83.7% for N-2. The contribution of PMMA to flow resistance was 2% and 11% for CO2 and N-2, respectively, and the contribution of graphene was 98% and 89% for CO2 and N-2. Therefore, this research presents a potential advance in transferring graphene to porous support, and the impermeability process of membranes composed of graphene/PMMA, a fundamental step for the development of graphene membranes before the production of controlled-sized pores.