Researchers develop enhanced graphene sieve that could advance clean water efforts

Vanderbilt engineers recently designed a simple defect-sealing technique to correct variations in pore size in graphene membranes. The researchers reported a breakthrough in scalable fabrication of graphene membranes with a sealing technology that corrects variations in the pore size so they remain small enough to trap salt ions and small molecules but allow water to pass.

Vanderbilt engineers design a defect-sealing technique to correct variations in pore size in graphene membranes image

One of the most complex engineering challenges when making membranes so thin is to maintain integrity in the uniformity of the pores, which requires drilling atomically precise holes in a one-atom thick sheet of carbon atoms. “A single large hole can cause high leakage and compromise membrane performance,” said Piran Kidambi, assistant professor of chemical and biomolecular engineering.

Chinese researchers develop graphene face mask for 48-hour use

Chinese researchers from AECC Beijing Institute of Aeronautical Materials (AECC BIAM) have developed a new type of face mask with graphene material on the key filter layer. The researchers have reportedly put a graphene-polypropylene material on the melt-blown fabric, which is the key filter layer of masks.

The graphene material is said to help the masks features stronger antibacterial properties, better air permeability and enhanced durability. The graphene face mask makes use of the nanoknife effect of the graphene material to destroy the cell wall of bacteria.

Researchers use graphene to resolve a known imaging impediment

Researchers at NIST have used a graphene membrane to solve a long-standing problem affecting the understanding of both living cells and batteries. When a solid and an electrically-conducting liquid come into contact, a thin sheet of charge forms between them. Although this interface, known as the electrical double layer (EDL), is only a few atoms thick, it plays a central role in a wide range of systems, such as keeping living cells nourished and maintaining the operation of batteries, fuel cells, and certain types of capacitors.

Graphene barrier solves imaging issue image

For instance, the buildup of an EDL on a cell membrane creates a difference in voltage between the liquid environs outside the cell and the cell's interior. The voltage difference draws ions such as potassium from the liquid into the cell, a process essential for the cell's survival and ability to transmit electrical signals.

Graphenea launches highly flat monolayer graphene on copper thin film

Graphenea has announced the launch of a new product – highly flat monolayer graphene. The graphene is grown by CVD on copper thin film on a 2” sapphire substrate. With extremely low roughness that is less than 4 nm, this new product is targeted at applications in photonics, high-performance electronics, magnetic memory, and freestanding membranes.

Graphenea's new flat monolayer graphene on copper thin film image

The product aims to meet wafer-scale integration requirements to build uniform graphene devices in a fashion compatible with current industrial fabrication methods. The flat graphene product is ready to be transferred by electrochemical delamination or dry methods since the sapphire substrate is robust enough to withstand mechanical damage, preventing tearing and wrinkling of the thin Cu sheet. The total wafer thickness is 430 micrometers. Full product information can be found in Graphenea's online store.

University of Manchester and Khalifa University collaboration uses GO to take salts out of water

A partnership between The University of Manchester and Khalifa University of Science and Technology in Abu Dhabi has yielded graphene-based membranes aimed at to taking salts out of water.

The most popular method for water desalination currently is a process called reverse osmosis, which requires large quantities of water to be forced through a membrane to remove the salts in the water. This method is particularly useful when there is a high salt content, however more efficient methods are required for bodies of water that have a lower salt content, known as brackish water. The team of researchers has developed new ion-selective membranes incorporating graphene oxide, for use in electromembrane desalination processes such as electrodialysis and membrane capacitive deionization.