Water desalination using graphene oxide-embedded paper microfluidics

Abstract

The need for the removal of salt constituents is very critical in several downstream processes of biological materials and saltwater purification. Substantial efforts to drive low cost-effective techniques for desalination are ongoing, and it is hopeful that novel nanomaterials could provide useful insight to a new paradigm in salt capturing both in biogenic fluids and complex solutions like seawater. In this report, we demonstrate a microfluidic proof-of-concept for a desalination system, in which graphene oxide deposited on the paper substrate was used to remove salt-ion concentration. Our investigation suggests that the optimal modification of paper with the five-time deposition of graphene oxide (paper@5GO) shows the best salt removal performance with the salt-rejection efficiency of ~ 97.0%. The salt rejection occurs by the phenomenon of surface adsorption on the GO-modified paper membrane which is confirmed by the detailed analytical studies of pre- and post-treatment. The system presented does not require additional energy input in the process and thus would become cost-effective and scalable with high salt removal efficiency which may be useful in bioanalysis and saltwater purification for sustainable development.