Advance On Wonder-Material Molybdenum Disulfide Brings Ultrathin Electronics Closer

Molybdenum disulfide, a new member of the ultrathin materials family, could have great potential to advance electronic and thermal devices by manipulating it with gold atoms that improve its electrical characteristics.

Vikas Berry, professor of chemical engineering at Kansas State University, and his research team have studied the new three-atom-thick material and say the finding could help to improve transistors, photodetectors, sensors and thermally conductive coatings. Even more exciting, it could also produce ultrafast, ultrathin logic and plasmonics devices.

Berry's laboratory has been leading studies on synthesis and properties of several next-generation atomically thick nanomaterials, such as graphene and boron-nitride layers, which have been applied for sensitive detection, high-rectifying electronics, mechanically strong composites and novel bionanotechnology applications.

"Futuristically, these atomically thick structures have the potential to revolutionize electronics by evolving into devices that will be only a few atoms thick," Berry said.

For the latest research, Berry and his team focused on transistors based on molybdenum disulfide, or MoS2, which was isolated only two years ago. The material is made of three-atom-thick sheets and has recently shown to have transistor-rectification that is better than graphene, which is a single-atom-thick sheet of carbon atoms.

When Berry's team studied molybdenum disulfide's structure, they realized that the sulfur group on its surface had a strong chemistry with noble metals, including gold. By establishing a bond between molybdenum disulfide and gold nanostructures, they found that the bond acted as a highly coupled gate capacitor.

Berry's team enhanced several transistor characteristics of molybdenum disulfide by manipulating it with gold nanomaterials.

The work may greatly improve future electronics, which will be ultrathin, Berry said. Importantly, it will also reduce the power that is required to operate these ultrathin devices.

"The research will pave the way for atomically fusing layered heterostructures to leverage their capacitive interactions for next-generation electronics and photonics," Berry said. "For example, the gold nanoparticles can help launch 2-D plasmons on ultrathin materials, enabling their interference for plasmonic-logic devices."

The research also supports the current work on molybdenum disulfide-graphene-based electron-tunneling transistors by providing a route for direct electrode attachment on a molybdenum disulfide tunneling gate.

The researchers plan to create further complex nanoscale architectures on molybdenum disulfide to build logic devices and sensors.

"The incorporation of gold into molybdenum disulfide provides an avenue for transistors, biochemical sensors, plasmonic devices and catalytic substrate," said Phong Nguyen, a doctoral student in chemical engineering, Wichita, Kan., who is part of Berry's research team.