Ultrathin, molecular-sieving graphene oxide membranes for separations along with their methods of formation and use

Patent metadata

Field	Value
Publication number	US-9795931-B2
Application number	US-201514738123-A
Country	US
Kind code	B2
Filing date	Jun 12, 2015
Priority date	Feb 14, 2013
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

Methods for forming an ultrathin GO membrane are provided. The method can include: dispersing a single-layered graphene oxide powder in deionized water to form a single-layered graphene oxide dispersion; centrifuging the graphene oxide dispersion to remove aggregated graphene oxide material from the single-layered graphene oxide dispersion; thereafter, diluting the single-layered graphene oxide dispersion by about ten times or more through addition of deionized water to the graphene oxide dispersion; and thereafter, passing the single-layered graphene oxide dispersion through a substrate such that a graphene oxide membrane is formed on the substrate. Filtration membranes are also provided and can include: a graphene oxide membrane having a thickness of about 1.8 nm to about 180 nm, with the graphene oxide membrane comprises about 3 to about 30 layers of graphene oxide flakes.

First claim

What is claimed:

1. A filtration membrane, comprising:
a porous substrate having a plurality of substrate pores; and
a graphene oxide membrane on the porous substrate, the graphene oxide membrane having a thickness of about 1.8 nm to about 180 nm, wherein the graphene oxide membrane comprises about 3 to about 30 layers of single-layered graphene oxide flakes, wherein the graphene oxide membrane has a plurality of membrane pores, and wherein the membrane pores are smaller than the substrate pores.

2. The filtration membrane of claim 1 , wherein the single-layered graphene oxide flakes have a size up to about 500 nm.

3. The filtration membrane of claim 1 , wherein the graphene oxide membrane has a thickness of about 1.8 nm to about 20 nm.

4. The filtration membrane of claim 1 , wherein the graphene oxide membrane has a thickness of about 1.8 nm to about 18 nm.

5. The filtration membrane of claim 1 , wherein the graphene oxide membrane comprises about 3 to about 10 layers of the single-layered graphene oxide flakes.

6. The filtration membrane of claim 1 , wherein the graphene oxide membrane has an area of about 4 cm 2 or greater.

7. The filtration membrane of claim 1 , wherein the porous substrate is an anodic aluminum oxide filter.

8. The filtration membrane of claim 1 , wherein the porous substrate defines pores having a pore size of about 20 nm to about 100 nm.

Assignees

• Univ South Carolina

Inventors

• Yu Miao
• Li Hang

Classifications

• B01D2325/12

  Adsorbents being present on the surface of the membranes or in the pores · CPC title

• B01D2325/04

  Characteristic thickness · CPC title

• B01D67/0046

  by slurry techniques, e.g. die or slip-casting · CPC title

• B01D71/021

  Carbon · CPC title

• B01D69/12

  Composite membranes; Ultra-thin membranes · CPC title