A multifunctional bi-phasic graphene oxide/chitosan paper for water treatment

•A biphasic Graphene oxide/chitosan paper was developed for water treatment.•The presence of chitosan renders high water stability to the hybrid structure.•The biphasic paper can absorb both anionic and cationic dyes and kill bacteria. A bi-phasic and water-stable GO paper was developed based on a simple casting method and the addition of a chitosan (CH) coating layer. While pure GO paper re-dispersed after water immersion water becoming a powder, the bi-phasic GO/CH paper presented water stability. The stable GO/CH paper was able to adsorb both anionic and cationic dyes showing a maximum monolayer adsorption capacity (qm) of 103 mg/g and 232 mg/g for Methylene Blue and Methyl Orange, respectively. The biocidal behavior of GO and CH was rendered to the paper presenting antibacterial capacity against Staphylococcus Aureus and Escherichia coli under continuous agitation. These results show that our GO/CH paper can be a viable material for water treatment.