Effect of surface charge density of graphene oxide on chemical warfare agent simulants blocking

[Display omitted] •The inner structure of GO film can be controlled based on the charge density of GO nanosheets.•The charge density of GO nanosheets depended on the size of GO sheets.•The narrow interlayer distance between GO sheets with high charge density was confirmed by cross-sectional TEM.•The narrow interlayer distance inhibited the penetration of DMMPs through the membrane by diffusion inhibition. Chemical warfare agents (CWAs) cause death, injury, temporary disability, and sensory stimulation when they come in contact with the skin or the respiratory system. CWAs move by diffusion; therefore, it is essential to control the pathways that they traverse. CWAs move through the spaces between graphene oxide (GO) sheets within a stacked GO film. Here, we demonstrate that GO nanosheets with high surface charge density offer protection performance. Our results reveal that the interlayer distance between the GO nanosheets depends on the surface charge density of the GO nanosheets. The protective effect of GO membranes is investigated using vapor transmittance rates (DVTRs) of dimethyl methylphosphonate (DMMP), a nerve gas simulant, and water vapor transmittance rates (WVTRs). The DVTR of GO membrane is decreased from 213.24 g/m2 day to 132.48 g/m2 day as the distance narrows. These results demonstrate that applying extremely thin GO membranes to protective clothing and masks can prevent the diffusion of CWAs even without special treatment.