Good news! A "giant" effect? 😊
Still, the million dollar question is how safe will be the handling of hydrogen overall? Remember, e.g. the Hindenburg disaster of 1937!
"Researchers have made a material capable of cooling substances down to -253°C – enough to liquefy hydrogen – using magnets.
They say their research ... could provide a cheaper and more sustainable way to supercool hydrogen fuel for storage and transport.
The researchers tapped into the “magnetocaloric effect”: applying magnetic fields to certain substances can change their temperature. ...
The pink crystals could cool to 20 Kelvin, or -253°C. Just 20°C above absolute zero, this is cool enough to prompt the condensation of hydrogen, rendering it a liquid. ..."
"... Blake used magnetocaloric cooling to reach 20°K, cold enough to liquify hydrogen. This has been done before, but only with materials containing rare-earth metals. ..."
From the abstract:
"Magnetic refrigeration, which utilizes the magnetocaloric effect, can provide a viable alternative to the ubiquitous vapor compression or Joule-Thompson expansion methods of refrigeration. For applications such as hydrogen gas liquefaction, the development of magnetocaloric materials that perform well in moderate magnetic fields without using rare-earth elements is highly desirable. Here we present a thorough investigation of the structural and magnetocaloric properties of a novel layered organic-inorganic hybrid coordination polymer Co4(OH)6(SO4)2[enH2] (enH2 = ethylenediammonium). Heat capacity, magnetometry and direct adiabatic temperature change measurements using pulsed magnetic fields reveal a field-dependent ferromagnetic second-order phase transition at 10 K << 15 K. Near the hydrogen liquefaction temperature and in a magnetic field change of 1 T, a large maximum value of the magnetic entropy change, = − 6.31 J kg−1 K−1, and an adiabatic temperature change,
= 1.98 K, are observed. These values are exceptional for rare-earth-free materials and competitive with many rare-earth-containing alloys that have been proposed for magnetic cooling around the hydrogen liquefaction range."
Magnetocaloric cooling method produces liquid hydrogen using environmentally friendly technology
Giant magnetocaloric effect in a rare-earth-free layered coordination polymer at liquid hydrogen temperatures (open access)
Fig. 1: Structure of Co4(OH)6(SO4)2[enH2].
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