Scientists have long assumed that the center of gas giants (planets do not have solid surfaces and are composed largely of hydrogen and other gases) the laws of physics of materials does not work as it does on other planets. In such conditions, under tremendous pressure hydrogen is compressed so much that literally becomes a metal. For many years researchers were looking for the ability to create metallic hydrogen in the laboratory for its unique properties that could be useful in many fields of human activity.
What benefits the person can bring metallic hydrogen? For example, they are useful in the manufacture of electronics of the future, due to its particular properties electrical conductivity. And based on it will be possible to make a new rocket fuel.
It is also interesting to read: Hydrogen and asteroids could engender a life on Mars.
How to get metallic hydrogen?
To date, the only available method of obtaining of metallic hydrogen is to use a special diamond anvils, where the hydrogen atoms are compressed and cooled until then, until you change their state. Almost 80 years scientists have been trying to turn hydrogen gas into metal and here they have succeeded. To do this, they apply pressure that is greater than that in the core of the Earth.
The publication of such results already appeared earlier, but no group of scientists could not confirm them. For example, in 2011 it was reported that scientists were able to “squeeze” the hydrogen to the desired state by the application of pressure above 220 GPA (GPA), which is more than 2 million times higher than atmospheric, which is 100 kPa (in kPa). In 2017, another group of scientists announced that they managed to achieve a pressure of 495 GPA. By the way, while the main part of the experiments they carry out not in time. The only received a sample of metallic hydrogen was lost after one of the diamond anvils were scattered in the dust while trying to measure the pressure. What became of the sample is unclear. Maybe he got lost among the diamond particles, may be turned back into gas. Read more about this failure here here.
French scientists have taken into account previous experience and mistakes of their colleagues, and their previous studies and still achieved the desired result. Managed it thanks to two discoveries. First, they changed the design of the diamond anvils, making the top of the diamond tips are not flat, and toroidal, with a recess in the form of a donut. This change allowed us to increase the maximum pressure limit from 400 HPa to 600 HPa.
The superior diamond tipped anvils. The diameter of annular cracks is about 150 microns (slightly greater than the thickness of a human hair)
Second, they created a new type of special infrared spectrometer allowing measurements of a sample of hydrogen.
In the experiment, the researchers began to compress in a diamond anvil sample of hydrogen and chill. When the pressure has reached 425 HPa, and the temperature was -193 degrees Celsius, hydrogen began to absorb infra-red radiation spectrometer. This was evidence of the transition of hydrogen to another solid state.
The picture of the transition phases of hydrogen in the experiment 2017 (top) and phase changes at different pressures – 315, 427 and 300 HPa – the experiment of the French scientists. In the second case, it is clear that the pattern of hydrogen became opaque
The statement of French scientists was viewed with distrust, in the main, because the previous statement about the successful creation of metallic hydrogen was found to be incorrect, untrue or simply unprovable.
However, now many say that a group of French physicists may get a Nobel prize for his discovery — the most prestigious award in science.