Research on molybdenum disulfide sparks new apps

MANHASSET, N.Y. -- Molybdenum disulfide, used for many years as an industrial lubricant, promises to become another 2-D platform for electronic devices on par with graphene, itself a 2-D platform for new electronic devices.

Last year scientists at the Swiss university EPFL produced a transistor on the MoS2 material. Meanwhile researchers at the Massachusetts Institute of Technology have succeeded in making a variety of electronic components from MoS2. The researchers claim the material could help usher in radically new products, from whole walls that glow to clothing with embedded electronics to glasses with built-in display screens.

“It’s the most exciting time for electronics in the last 20 or 30 years,” said Tomás Palacios, the Emmanuel E. Landsman Associate Professor of EECS who thinks graphene and MoS2 are just the beginning of a new realm of research on two-dimensional materials.

The MIT researchers found making progress with graphene difficult because that material lacks a bandgap, and MoS2 comes with one.

The lack of a bandgap means a switch made of graphene can be turned on, but not off. "That means you can’t do digital logic,” said researcher Han Wang.

Researchers have been searching for a material that shares some of graphene’s extraordinary properties and has a bandgap, and molybdenum disulfide does.

Wang and Palacios were able to fabricate an inverter; a NAND gate; a memory device; and a ring oscillator, made up of 12 interconnected transistors, which can produce a precisely tuned wave output.

Also, by using one-molecule thick MoS2 material for transistors in large-screen displays to control each pixel of a display eliminates millions of atoms-thick silicon used in conventional transistors, potentially reducing cost and weight and improving energy efficiency, claim the researchers.

Further on, the material could be used, in combination with other 2-D materials, to make light-emitting devices lighting up an entire wall as well as for antenna and other circuitry of a cellphone being woven into the fabric of clothing, according to the researchers.

The MIT work was funded by the U.S. Office of Naval Research, the Microelectronics Advanced Research Corporation Focus Center for Materials, the National Science Foundation and the Army Research Laboratory.

A paper has been published online this month in the journal Nano Letters.