Researchers from Japan, China, and Taiwan have developed a graphene oxide (GO) membrane with embedded nanodiamonds for purifying hydrogen from water vapor, according to InScience.
As a result of the water vapor produced during hydrogen production, it is common for hydrogen to have a high relative humidity. Hydrogen gas is purified through the use of membranes. However, this is a time- and money-consuming process.
Graphene oxide (GO) can be used to clean gases because its membranes are extremely permeable and selective. Because of this, membranes for hydrogen purification could benefit from their development. However, this is not the case when attempting to separate water vapor, as graphene loses all of its beneficial properties when moist.
Water vapor enters the space between the negatively charged graphene layers and dissolves the membrane as a result of the layers’ mutual repellency.
When positively charged nanodiamonds are incorporated into membranes, the graphene layers stop repelling each other and dissolve in water, as demonstrated by a team of scientists in their study.
After just one cleaning pass, graphene membranes fail, but the GO composite with nanodiamonds retain their properties after repeated cycles of cleaning.
This type of membrane has been successfully used in air conditioners, semiconductor manufacturing, and lithium-ion battery production, among other fields, to remove excess moisture from the air.
