Molybdenite’s Thermal Conductivity Measured for First Time

Molybdenum disulfide, also known as molybdenite, has been gaining more and more attention in the tech space of late as researchers use the material to improve digital cameras, sodium-ion batteries and more. 

However, until now, no one has been able to measure the material’s thermal conductivity. That’s a problem, Angela Hight Walker of the Physical Measurement Laboratory’s Semiconductor and Dimensional Metrology Division, told Phys.org, because “[m]easurement of thermal conductivity is an absolutely critical step in the evaluation of a material for applications in electronics — or anywhere else, for that matter.”

What is molybdenite?

Put simply, molybdenite is a 2D material that is only a few nanometers thick, as per Phys.org. It’s notable for being similar to graphene, another 2D material whose much-lauded characteristics include being a better electricity conductor than copper, impermeable to gases and 200 times stronger — but six times lighter — than steel.

Indeed, molybdenite was once considered a possible rival to graphene. The thinking behind that, according to IEEE Spectrum, was that “the material’s intrinsic rather than engineered band gap” gave it “an edge as a transistor material.” Since then, the shine has come off molybdenite somewhat, largely because researchers have realized that it has “less-than-ideal mobility and sub-threshold slope.” However, as noted above, the material does have its uses.

How did they do it?

Phys.org explains that Hight Walker, along with her team, discovered how to measure molybdenite’s thermal conductivity using a technique called Raman spectroscopy. That involves shining a monochromatic laser light onto a sample of the material and detecting the scattered light. “The frequency of the scattered light depends on the way the material stretches and vibrates,” the news outlet notes, “and during imaging temperature affects these vibrations.”

To study the effect of temperature, the researchers both heated the sample environment and increased laser power onto the sample, ultimately discovering that molybdenite is “about 100 times less efficient at conducting heat than graphene.” That said, it’s fairly easy to model the material’s thermal response.

Discovery impact

As mentioned, being able to measure molybdenite’s thermal conductivity is mainly important because it will help those in the tech sector determine which electronics applications the material can be used in.

Some specific applications are already in the works. As Phys.org notes, “[t]he findings may hasten the use of moly — alone or in combination with other 2D materials — in new electronic devices, or other anticipated uses such as water-splitting for hydrogen generation and improved electrodes for lithium-ion batteries.”

Tech fiends would thus do well to keep an eye out for further molybdenite developments.

Securities Disclosure: I, Charlotte McLeod, hold no direct investment interest in any company mentioned in this article. 

Related reading: 

Molybdenum Goes Far Beyond Steelmaking

Molybdenite Making Waves in Electronics, Green Technology

Molybdenite and Graphene Combine for Sodium-ion Battery Fix