_TECHNOLOGY Materials

_Atomic Sandwiches

Drexel engineers’ recipe for ‘sandwiching’ atomic layers expands the possibilities for making materials that store energy.

_Babak Anasori

Anasori is a research associate in the A.J. Drexel Nanomaterials Institute.

The scientists whose job it is to test the limits of what nature — specifically chemistry — will allow to exist just set up shop on some new real estate on the Periodic Table.

Using a method they invented for joining disparate elemental layers into a stable material with uniform, predictable properties, Drexel researchers are testing an array of new combinations that may vastly expand the options available to create faster, smaller, more efficient energy storage, advanced electronics and wear-resistant materials.

Led by A.J. Drexel Nanomaterials Institute Research Associate Babak Anasori, a team from the Department of Materials Science and Engineering created the material-making method that can sandwich two-dimensional sheets of elements that otherwise couldn’t be combined in a stable way. And they proved its effectiveness by creating two entirely new, layered 2-D materials using molybdenum, titanium and carbon.

MIX_AND_MATCH

Drexel researchers have made several new layered materials and predict that they can make as many as 25 new combinations using their new method for atomic “sandwiching.”

“By ‘sandwiching’ one or two atomic layers of a transition metal like titanium between monoatomic layers of another metal, such as molybdenum, with carbon atoms holding them together, we discovered that a stable material can be produced,” Anasori explains. “It was impossible to produce a 2-D material having just three or four molybdenum layers in such structures, but because we added the extra layer of titanium as a connector, we were able to synthesize them.”

The discovery was recently published in the journal ACS Nano. It’s significant because it represents a new way of combining elemental materials to form the building blocks of energy storage technology — think batteries, capacitors and supercapacitors, as well as superstrong composites, like the ones used in phone cases and body armor. Each new combination presents new properties and researchers suspect that one, or more, of these new materials will exhibit energy storage and durability properties so disproportional to its size that it could revolutionize technology.