Solid metallic hydrogen has been produced in the laboratory
arxiv.org
arxiv.org
Incredible technology!
> The pressure was initially determined to ~88 GPa by ruby fluorescence using the scale of Chijioke et al (20); the exciting laser power was limited to a few mW. At higher pressures we measured the IR vibron absorption peaks of hydrogen with a Fourier transform infrared spectrometer with a thermal IR source, using the known pressure dependence of the IR vibron peaks for pressure determination (see SM).
Just incredible!
> Photos were taken with a smartphone camera at the ocular of a modified stereo microscope
...
Still incredible! We as people tend to underestimate just how "magical" our mobile phones are.
> Moreover, SMH (solid metal hydrogen) is predicted to be metastable so that it may exist at room temperature when the pressure is released. If so, and superconducting, it could have an important impact on mankind’s energy problems and would revolutionize rocketry as a powerful rocket propellant.
> The principal limitation for achieving the required pressures to observe SMH in a DAC (diamond anvil cell) has been failure of the diamonds.
> The sample was cryogenically loaded at 15 K and included a grain of ruby for pressure determination.
> As of the writing of this article we are maintaining the first sample of the first element in the form of solid metallic hydrogen at liquid nitrogen temperature in a cryostat.
The first production of metallic oxygen was a liquid, this is the first solid one, tho at these pressures it's really unlikely that it would effective as fuel store. One of the more interesting parts about metallic hydrogen is the information we learn also applies to hydrides (hydrogen alloys) especially things like Lithium-Hydrogen since basically you can stabilize a large amount of hydrogen atoms (6 or more) around a single atom of Lithium, this might actually be very interesting for a lot of applications including energy storage. Hydrides should be considerably more stable and more importantly at considerably lower pressures which would mean that they can actually be used for various applications since you are not going to find something that only can exist at 400 gPA levels of pressure or higher very useful for high stress applications.
The problem with hydrogen as fuel storage (mainly for space travel) is the pressure, operating a fuel tank at 400 gPA or higher is going to be tricky, I've edited my previous post and added the bit about Hydrides which might actually considerably more viable for both terrestrial and space applications.
If we can actually make LiH6 alloys and can find an easy way to break them apart it can be a great fuel source, yes we might have to carry some "dead weight" but Li has an atomic number of 3 Oxygen has an atomic number of 8, considering that Hydrogen-Oxygen reaction is pretty much 1 to 1 (well "2") we have to carry considerably more Oxygen now than we would have to carry Lithium. If a Hydrogen-Hydrogen reaction could be harvested as a propellant it would still be more effective than what we have even if we don't find any clever ways of catalyzing the lithium we already carry to push the reaction even further, we might be able to carry a smaller amount of oxygen also to catalyze the lithium tho I'm not sure if the energy from that reaction would be worth the added weight of the oxygen and the parts of the fuel and propulsion systems that would support it and the O-Li process.
P.S.
Metallic hydrogen is also of "interest" to those who still study cold fusion, even tho you can't call it cold fusion any more due to the stigma, at certain conditions there is a high likelihood of Inertial Confinement Fusion and Pycno Nuclear Fusion occurring, this often brought up as "superconductor fusion" simply because you can't call anything cold fusion and get it published.
That might also be a quite interesting fuel source, especially if you simply need to push it to a certain limit and once the fusion kicks in it would transition to other fusion stages.
And lastly this might be especially interesting if we can make Li-Deuterium alloys since D-Li fusion produces Helium 4 and over 20 MeV of energy :)
This (last) type of fusion is extremely interesting because not only it's highly energetic but it's aneutronic, which means that less than 1% of the energy is released via neutrons vs 80-90% in other forums of fusion, aneutronic fusion produces tons of energy an pretty much no ionizing radiation which means if you can make it work it would be in theory a safe enough battery to power a cellphone without frying your brain.
Operating a fuel tank at 1 MPa is tricky. Operating a fuel tank at 400 GPa is ludicrous.
There's an interesting instructional video about this on Youtube: https://www.youtube.com/watch?v=uZwYMyHlWXk
"Moreover, SMH is predicted to be metastable so that it may exist at room temperature when the pressure is released (10). If so, and superconducting, it could have an important impact on mankind’s energy problems and would revolutionize rocketry as a powerful rocket propellant (11)."
http://www.projectrho.com/public_html/rocket/enginelist.php#...
Literally!
If I understand it correctly most of the energy (apart form E=mc^2 energy that can't be tapped easily) is what comes from the mechanical work squishing the hydrogen down to size.
That means the energy density should be in the order of the pressure, which is 495 GPa. So a cubic metre of the stuff would have half a terajoule of energy. Wikipedia says the Nagasaki bomb was about 90 terajoules.
If the stuff behaves in a simple way, you can release the energy by just releasing the pressure. If it is "metastable" that means it can somehow remain compressed when the pressure is released -- but will be "trying" to explode to its uncompressed state. We don't know if the metastable state even exists, let alone how easy it is to get out of.
https://www.sciencenews.org/article/pressure-make-metallic-h...
> A few months later, Silvera’s group squeezed hydrogen hard enough to make it nearly opaque, though not reflective — not quite a metal. “We think we’re just below the pressure that you need to make metallic hydrogen,” Silvera says. His findings are consistent with Eremets’ new phase, but Silvera disputes Eremets’ speculations of metallicity. “Every time they see something change they call it metallic,” Silvera says. “But they don’t really have evidence of metallic hydrogen.”
> All this back and forth may seem chaotic, but it’s also a sign of a swiftly progressing field, the researchers say. “I think it’s very healthy competition,” Gregoryanz says. “When you realize that somebody is getting ahead of you, you work hard.”
Not by Jove - inside Jove.
https://science.nasa.gov/science-news/science-at-nasa/2011/0...
The aliens working undercover among us now are rolling their 7 photoreceptors at our anthropocentrism.
Liquid Metallic hydrogen in Jupiter's core: https://science.nasa.gov/science-news/science-at-nasa/2011/0...
I sent him an email saying 'hey, isn't this what your PhD was on?'. Then, I looked up his thesis and saw that this was his thesis and, but this publication was from his lab, with his advisor as co-author.
Oh man. I hope I didn't cause any existential dread. He didn't just make a decision that cost him a Nobel, right?
So we need to approximate our solutions to be able to get a good idea of what properties a material will have. Our approximations are pretty good and we have a decent idea of when some things superconductor. But our theories of superconduction aren't yet perfect, and sometimes the approximations can fail//generate behavior unexpected by our theories.
Standard atmospheric pressure ~= 100Pa
So they increased the pressure in that chamber by 4.95billion times.
And then they hypothesise that the hydrogen metal could be stable at room temperature.
Oh. My. Days.
As I said, I'm genuinely curious. I'm not even an amateur here, but I wouldn't have thought to ask this at all.
So for this to be exciting we first need the even more exciting news that MH is metastable so that we can release the pressure. Then we can find out if we have a high temperature, high explosive, superconductor.
Even that is probably not of practical use. But by gum! It'd be fun.