TY - JOUR
T1 - Solvent transport behavior of shear aligned graphene oxide membranes and implications in organic solvent nanofiltration
AU - Akbari, Abozar
AU - Meragawi, Sally E.
AU - Martin, Samuel T.
AU - Corry, Ben
AU - Shamsaei, Ezzatollah
AU - Easton, Christopher D.
AU - Bhattacharyya, Dibakar
AU - Majumder, Mainak
PY - 2018/1/17
Y1 - 2018/1/17
N2 - Solvent transport in membranes composed of stacked sheets of graphene oxide (GO) with molecular scale channels and a complex arrangement of hydrophobic and hydrophilic domains is not well understood. Here, we observe that the interlayer space between GO sheets expands in different solvents without disturbing the membrane integrity and is typically larger in aqueous media compared to nonaqueous media. However, the membranes have a tighter molecule sieving feature in aqueous media as demonstrated by lower permeance and higher solute rejection arising from interfacial water layers "sticking" to charged polar groups. As a result of this polar interaction, the permeance of polar solvents in GO membrane scales inversely to the polarity of the solvent, which is contrary to other polymeric and ceramic hydrophilic membranes and also scales inversely to the viscosity of solvents as per continuum expectations. We highlight the extended solvent-handling space of GO membranes, such as in polar protic, polar aprotic, and nonpolar solvents, demonstrating versatility over a commercial nanofiltration membrane, and we predict exciting new applications in advanced separation engineering.
AB - Solvent transport in membranes composed of stacked sheets of graphene oxide (GO) with molecular scale channels and a complex arrangement of hydrophobic and hydrophilic domains is not well understood. Here, we observe that the interlayer space between GO sheets expands in different solvents without disturbing the membrane integrity and is typically larger in aqueous media compared to nonaqueous media. However, the membranes have a tighter molecule sieving feature in aqueous media as demonstrated by lower permeance and higher solute rejection arising from interfacial water layers "sticking" to charged polar groups. As a result of this polar interaction, the permeance of polar solvents in GO membrane scales inversely to the polarity of the solvent, which is contrary to other polymeric and ceramic hydrophilic membranes and also scales inversely to the viscosity of solvents as per continuum expectations. We highlight the extended solvent-handling space of GO membranes, such as in polar protic, polar aprotic, and nonpolar solvents, demonstrating versatility over a commercial nanofiltration membrane, and we predict exciting new applications in advanced separation engineering.
KW - graphene
KW - graphene oxide
KW - membrane
KW - nanofiltration
KW - organic solvent
KW - solvent transport
UR - http://www.scopus.com/inward/record.url?scp=85040653294&partnerID=8YFLogxK
U2 - 10.1021/acsami.7b11777
DO - 10.1021/acsami.7b11777
M3 - Article
AN - SCOPUS:85040653294
SN - 1944-8244
VL - 10
SP - 2067
EP - 2074
JO - ACS Applied Materials & Interfaces
JF - ACS Applied Materials & Interfaces
IS - 2
ER -