Science

Metal-based graphene alternative "shines" with promise

Metal-based graphene alternati...
A rolled film of the material – the roll is about one tenth the diameter of a human hair
A rolled film of the material – the roll is about one tenth the diameter of a human hair
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A rolled film of the material – the roll is about one tenth the diameter of a human hair
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A rolled film of the material – the roll is about one tenth the diameter of a human hair

With its incredible strength, chemical stability, high thermal conductivity and low electrical resistance, it's no wonder that graphene is finding more and more uses. Soon, however, it may be facing some competition from molybdenum di-sulphide – a thin metallic film that can emit light.

Graphene consists of a one-atom-thick sheet of carbon atoms, arranged in a honeycomb pattern. Molybdenum di-sulphide (MoS2), on the other hand, is made from a mixture of molybdenum and sulphur.

It's a member of a family of materials known as transition metal di-chalcogenides, or TMDCs. These possess some of graphene's desirable qualities (such as mechanical strength and electrical conductivity), plus they can also emit light – this means that they could find use in things like photodetectors or light-emitting devices.

Unfortunately, it has previously proven difficult to produce TMDCs in forms any larger than flakes measuring only a few hundred square microns in area. Now, however, Dr. Kevin Huang from the University of Southampton has announced the fabrication of MoS2 films that are just a few atoms thick, but that have an area of over 1,000 square millimeters. What's more, they can reportedly be transferred to almost any substrate.

The films were produced using a chemical vapor deposition process, that Huang and his team have been exploring since 2001.

"Being able to manufacture sheets of MoS2 and related materials, rather than just microscopic flakes, as previously was the case, greatly expands their promise for nanoelectronic and optoelectronic applications," he said.

A paper on the research was recently published in the journal Nanoscale.

Source: University of Southampton

9 comments
Brian Mcc
Name one product that has Graphene in it. One that's commercially available. If its sooo wonderful you would think products would be on the market by now.
Strings
@Brian Mcc As with any new material, production needs to ramp up--and it will go into business products before you see it in consumer products. That said, it is already seeing a few industry uses. Lockheed is preparing to launch a graphene nanopore water filter. There's a graphene based fluid for oil and gas exploration, there's a graphene based conducting ink for industrial 3D printers... Honestly, most of them you will never even hear about. Give it about seven to ten years to filter down to the consumer level.
Nairda
I know on the surface these super materials appear as dangerous as graphite powder. Just hope nature doesn't give us a backhand like we received from other materials like asbestos that at time of discovery were also seen as wonder materials.
ezeflyer
Nanomaterials are a health and environmental hazard. Does anybody care?
Phyzzi
Fullerines are in all kinds of things. Sheets of pure graphine generally are better for research applications (not necessarily as the subject of the research but as a tool to use in making measurements) it's not actually that surprising that it's seen limited exposure in consumer products. Pretty much anything that generates visible light and has some form factor advantage can be moved into industry in 5 years. Who knows if that will indeed be the case here (it depends on whether the advantage of using it is worth the retooling cost) but it's worth keeping in mind.
Gadgeteer
I think you alarmists are a little too paranoid. Molybdenum disulfide has been in widespread use for a very long time. It's a very common lubricant. This is just scaling it up to large sheets rather than microscopic particles.
Keith Reeder
"Nanomaterials are a health and environmental hazard. Does anybody care?" Well you obviously do - I feel safer already, The fact is that ANYTHING - not just nanomaterials - can be a health or environmental hazard in the wrong place, at the wrong time, and use in wrong way. Besides, so far only Copper Oxide has been demonstrated to carry a health risk. A little less knee-jerk alarmism about them would probably be a good thing. To quote the OECD on the subject: "As with other chemicals, it is clear that each nanomaterial may pose specific challenges, but in most instances, they can be addressed with existing test methods and assessment approaches"
GRich
Seems to me that making 2 dimensional materials is as difficult as building a house out of a deck of cards and then carefully spray on super glue without creating a gust strong enough to knock it down. From what I read about Graphene, this 2 dimensional carbon structure loses some of it's wonderful properties when it 3 dimensionally bonds with neighboring materials or itself except under certain configurations which keep them isolated from each other. The fact that MoS2 was difficult to produce in 2d form larger than small flakes suggests that it also wants to bond 3 dimensionally. Therefore, making products which can exploit superior properties such as high strength, conductivity, etc.... will require careful tweaking to preserve the qualities we want from it for a reliable amount of time to be worth paying for.
Michael Flower
Should make GREAT LIGHTWEIGHT ARMOR, for Car, Spaceships, Submarines, Airplanes, Ship-Board Armor, etc. With a impact resistance of 150,000,000-psi (or a 1-grain weight projectile traveling at 0.003c or 899,377.374m/s). Now, all we need is a "Plasma Shield" as the 1st-Line of defense.