Scientists May Have Made Metallic Hydrogen, a Potentially Game-Changing Fuel Source

That piece of shiny metallic hydrogen is still stuck between the anvils and the two scientists said they can not remove it yet for fear that it will completely disintegrate.

Science professor Isaac Silvera and his postdoctoral fellow Ranga Dias say they’ve created metallic hydrogen for the first time. This is literally material that has never existed before.

However, before metallic hydrogen is used, researchers would first have to gauge whether the metallic hydrogen particle can survive at normal temperature.

Metallic hydrogen first theorized by Eugene Wigner and Hillard Bell Huntington in 1935. In simple terms, the normally transparent material would become shiny and reflective, and have other properties associated with metals. Paul Loubeyre, a physicist at France’s Atomic Energy Commission in Bruyères-le-Châtel urged the researchers to redo their measurements of the pressure.

“There have been dozens of theoretical papers and they all have different critical pressures for when it becomes metallic”, Silvera said. ‘In high pressure research things aren’t always well calibrated, ‘ Silvera says. But at that pressure, even the ultrahard diamonds can still shatter if they’re not perfectly smooth and virtually flawless. Again, this could dramatically reduce the costs of transferring electrical currents, meaning more powerful and efficient electric motors, and a far more efficient electrical grid.

Normally, researchers use diamonds dug from the Earth, which have tiny inconsistencies in their internal structure.

Crushing hydrogen so comprehensively means squeezing it between micrometre-scale points in diamond anvil cells (DACs).

Silvera said that the solution was to use a reactive ion etching process to shave a small layer – just five microns thick, or a tenth of the thickness of a human hair – from the surface of the diamond.

“I immediately said we have to make the measurements to confirm it, so we rearranged the lab … and that’s what we did”.

Hydrogen can be cryogenically frozen into a liquid, and by ramping up the pressure, transformed into a non-metallic, non-conductive solid.

Image of diamond anvils compressing molecular hydrogen. The sketches below show a molecular solid being compressed and then dissociated to atomic hydrogenR. Follow-up tests confirmed that the material was, indeed metallic.

But achieving such high pressures isn’t easy.

Professor Silvera and his fellow scientist fellow Ranga Dias squeezed a sample of frozen hydrogen to almost 72 million pounds per square inch, which is greater than the pressure at the center of the Earth.

Yet, with this achievement long prized in the high pressure science community, Silvera’s rival experimentalists have responded with extreme scepticism.

At about 335 gigapascals the hydrogen turned black, indicating a transition to a known form of the element that absorbs light. This, the team says, is a clear sign the hydrogen has turned metallic. Levitating trains come to mind. Converting metallic hydrogen back to its molecular form would also release an enormous amount of energy that could propel rockets to make outer space exploration easier. He also questions whether the Harvard team even saw metallic hydrogen, and suggests they might instead be measuring a rhenium gasket used in the DAC.

Hydrogen is the lightest of elements; each atom consists only of one proton and one electron.

But the prospect of this bright future could be at risk if the scientists’ next step – to establish whether the metal is stable at normal pressures and temperatures – fails to go as hoped.