Mighty MXenes are ready for commercial launch

Good news! A very impressive new material. Let's see what happens next! They claim this time it will be different! This is a very long, interesting article; did not have time to read it all!

"IN BRIEF

Researchers at Drexel University discovered MXenes, a new family of 2D materials, in 2010. The scientists soon found ways to prepare what seemed like endless chemical compositions of these materials, many with unique properties. Now studied by researchers worldwide, MXenes may soon play a transformative role in energy storage, electronics, optics, biomedicine, and catalysis. Many companies have MXene licenses and patents, and companies are on the verge of launching the first commercial products. But to make a real impact, researchers must tailor MXenes to improve their chemical stability and identify ways to manufacture them inexpensively at large scale. ...

The Drexel team dubbed the nanomaterial, formula Ti3C2, a MXene (pronounced “maxine”) given its similarity to graphene, which was all the rage at that time. There are dozens of MAX phases ... “We knew if we could do this for all MAX phases, we would have a huge family of 2D materials. We knew we had something big.” ...

Labs around the world caught on soon after the Drexel team reported the first MXene in 2011 ... and the MXene family a year later ... Since then, scientists have discovered more than 50 MXene compositions. Computers have predicted thousands more. Nowadays, about 70,000 scientists from 100-plus countries study MXenes. Research organizations dedicate scientific symposia and special issues of journals to the materials.

Research papers list a staggering range of potential applications: long-lasting batteries, flexible and wearable electronics, gas sensors, antennas, catalysts, photodetectors, and devices for water purification, green hydrogen production, and kidney dialysis.

Nearly 15 years since their discovery, MXenes are on the verge of commercial debut. Big corporations such as Samsung and Intel have MXene-related patents. And the Japanese electronic component manufacturer Murata Manufacturing plans to launch a MXene-based product within the next 3 years, a spokesperson says. ...

The discovery of an entirely new material is a rare event. The big materials discovery of the 20th century was fullerenes in 1985. In the early years of the 21st century [2004], graphene shook the materials world ... Graphene’s unique electronic and mechanical properties and the ease of making it in the lab quickly made it the darling of the materials community.

Twenty years and billions of R&D dollars since graphene’s discovery, however, the material’s use is limited. A few companies make heat sinks for mobile phones and niche sports products with graphene-based composites. But a groundbreaking application remains elusive. ...

Consider their mind-boggling tunability. The materials are layer cakes containing two to five layers of transition metals connected by one to four layers of nonmetal atoms. The general formula is Mn + 1XnTx, where n varies from 1 to 4, and Tx (x is variable) indicates terminations on the surface of the outer transition-metal layers. Those terminations can be oxygen, hydroxyls, amines, halogens, and chalcogens. ...

MXenes without surface terminations are conductive, like metals. But alter the type of transition metal or tailor the surface chemistry, and MXenes behave like semiconductors ...

From the transition metals that make up MXenes’ core, the materials inherit useful redox properties: the ability to take up, release, and rearrange electrons to enter various oxidation states. These properties underpin the electrochemical energy-storing reactions in batteries and electrocatalysis.

Then there are the physical traits. MXenes are exceptionally durable, elastic, and hydrophilic. Researchers can disperse MXene flakes in water and organic solvents to make inks. They can print and spray these inks to pattern MXene-based devices on curved, flexible surfaces or soak them into fabrics. ..."

Mighty MXenes are ready for launch Nearly 15 years after their discovery, the 2D materials are close to market. But will they find their killer app?

Researchers start with conductive materials called MAX phases, which are carbides or nitrides (X) of transition metals (M) interleaved with A-group elements (A). They can then make a seemingly endless variety of 2D MXenes by removing the A-group elements and adding various surface terminations (Tx) on the outer metal layers.