Non-covalent cross-linking to boost the stability and permeability of graphene-oxide-based membranes

Abstract

Non-covalent cross-linking is effective in boosting the stability and permeability of graphene-oxide-based membranes.

Elucidating Ultrafast Molecular Permeation through Well‐Defined 2D Nanochannels of Lamellar Membranes

“…Inserting neutral glycol does not alter the channel size, whereas the addition of ethanediamine or HCl efficiently reduces the size to about 1.0 nm because of their charge neutralization of Ti 3 C 2 T x . This manifests the important effect of interlayer interactions on channel size, which has been roughly regulated by physical insertions …”

“…Moreover, these nanochannels exhibit excellent stability when soaking in water and organics for more than 12 h (Supporting Information, Figure S20). While the construction of highly regular and robust 2D nanochannels is often difficult and even impossible for flexible nanosheets including graphene, GO, and g ‐C 3 N 4 nanosheets …”

Ultrahigh permeance of a chemical cross-linked graphene oxide nanofiltration membrane enhanced by cation–π interaction

“…In the practical application of GO nanoltration membranes, the interlayer spacing between the neighboring GO nanosheets, water ux, efficient rejection and stable performance of the membrane are all crucial in water purication. 6,7 However, the GO membrane is prone to swelling in water due to the large number of hydrophilic oxygen functional groups, which is not conducive to the stable performance of GO membrane in practical application. 8 There have been many effective efforts to stabilize the interlayer spacing and prevent the swelling tendency of GO membranes.…”

Elucidating Ultrafast Molecular Permeation through Well‐Defined 2D Nanochannels of Lamellar Membranes

“…While the construction of highly regular and robust 2D nanochannels is often difficult and even impossible for flexible nanosheets including graphene,G O, and g-C 3 N 4 nanosheets. [9,10] Nanosheet functionalization affords tunable wettability for membranes ( Figure 2f). Rich À OH groups endow Ti 3 C 2 T x membrane with strong hydrophilicity (water contact angle, 19.88 8).…”

“…Inserting neutral glycol does not alter the channel size,w hereas the addition of ethanediamine or HCl efficiently reduces the size to about 1.0 nm because of their charge neutralization of Ti 3 C 2 T x .This manifests the important effect of interlayer interactions on channel size,w hich has been roughly regulated by physical insertions. [9,10] Membrane structure is further probed by variable-energy positron annihilation spectroscopy (Figure 2d), which depicts that the S parameter first decreases (lamellar layer) and then increases (support layer) for membranes.A ccordingly,t he mean implantation depth (R,n m) is calculated to be about 325 nm, which matches the thickness of lamellar layer (Supporting Information, Figure S16). The S parameter values of lamellar layer roughly obey the order of Ti 3…”