Ultrahigh water permeance of a reduced graphene oxide nanofiltration membrane for multivalent metal ion rejection

We develop a kind of pure rGO membrane using amino-hydrothermal reduction that exhibits an ultrahigh water permeance of 142.5 L m −2 h −1 bar −1 while still maintaining a high rejection rate of 91.6% for multivalent metal ions. The prepared rGO membranes have two types of spacing: larger hydrophilic spacing and smaller hydrophobic spacing, resulting in superior filtration performance. This provides a new avenue for multivalent metal ion separation using pure rGO membranes. A simple way to fabricate pure rGO membranes shows ultrahigh water permeance and excellent multivalent metal ion rejection, as well as long-term stability.