Update of 3/11/2023: In the meantime I learnt that the same researcher has apparently done controversial things before and that an earlier paper with similar claims was retracted only a few months ago or so.
If confirmed, then this is huge!
Even if this was another premature announcement, it appears we are coming closer to this holy grail! It might happen any day!
Would a room temperature superconductor finally put the Global Warming hoax and Climate Change religion to rest and make it fade away as one of those human fads and follies? You bet!
"Companies could one day make superconductive quantum computer chips that function at room temperature thanks to a new material from researchers in the US. Ranga Dias from the University of Rochester and colleagues made a material superconductive at 21°C and pressures less than 1% of those used for existing high-temperature superconductors. ‘The most exciting part is the pressure,’ Dias tells Chemistry World. ‘Even I didn’t think this was possible.’
Together with Ashkan Salamat’s team at the University of Nevada, Las Vegas, the scientists say that electrical resistance in their nitrogen-doped lutetium hydride falls to zero at room temperature. Making room-temperature zero-resistance materials is a chemistry ‘holy grail’ and could fight climate change by reducing the 5% of electricity lost as heat while flowing through the grid. ...
However, Dias and Salamat’s team hasn’t been able to fully confirm the new material’s structure. As hydrogen atoms are so small they don’t easily diffract the x-rays used to work out the material’s composition. And this is an important reservation, considering the publisher of the team’s previous high-temperature superconductor paper retracted it. ...
Many questions remain ...
However, Dias and Salamat’s team hasn’t been able to fully confirm the new material’s structure. As hydrogen atoms are so small they don’t easily diffract the x-rays used to work out the material’s composition. And this is an important reservation, considering the publisher of the team’s previous high-temperature superconductor paper retracted it. ...
Many questions remain ...
For Mikhail Eremets from the Max Planck Institute for Chemistry in Mainz, Germany, whose team first produced hydrogen sulfides that are superconducting at high temperatures, the work’s reproducibility is of ‘paramount importance’. His team has reproduced Dias and Salamat’s team’s previous material, but without the same performance. He is encouraged by the seemingly simple preparation conditions but concerned by an ‘alarming’ note in the paper calling the synthesis ‘extremely complex’. ‘I hope and find it important that this time the authors and the journal will provide all necessary information and support for smooth reproduction of the sample and the results,’ he adds. ..."
From the abstract:
"The absence of electrical resistance exhibited by superconducting materials would have enormous potential for applications if it existed at ambient temperature and pressure conditions. Despite decades of intense research efforts, such a state has yet to be realized. At ambient pressures, cuprates are the material class exhibiting superconductivity to the highest critical superconducting transition temperatures (Tc), up to about 133 K. Over the past decade, high-pressure ‘chemical precompression’ of hydrogen-dominant alloys has led the search for high-temperature superconductivity, with demonstrated Tc approaching the freezing point of water in binary hydrides at megabar pressures. Ternary hydrogen-rich compounds, such as carbonaceous sulfur hydride, offer an even larger chemical space to potentially improve the properties of superconducting hydrides. Here we report evidence of superconductivity on a nitrogen-doped lutetium hydride with a maximum Tc of 294 K at 10 kbar, that is, superconductivity at room temperature and near-ambient pressures. The compound was synthesized under high-pressure high-temperature conditions and then—after full recoverability—its material and superconducting properties were examined along compression pathways. These include temperature-dependent resistance with and without an applied magnetic field, the magnetization (M) versus magnetic field (H) curve, a.c. and d.c. magnetic susceptibility, as well as heat-capacity measurements. X-ray diffraction (XRD), energy-dispersive X-ray (EDX) and theoretical simulations provide some insight into the stoichiometry of the synthesized material. Nevertheless, further experiments and simulations are needed to determine the exact stoichiometry of hydrogen and nitrogen, and their respective atomistic positions, in a greater effort to further understand the superconducting state of the material."
Evidence of near-ambient superconductivity in a N-doped lutetium hydride (no public access???)
The nitrogen-doped lutetium hydride starts out blue, then turns pink as pressures increase to the point where it becomes superconducting, and then turns red as pressure increases further.
An approximately one millimeter diameter sample of lutetium hydride, a superconducting material created in the lab of Rochester scientist Ranga Dias, seen though a microscope. This composite image is the result of focus stacking and color-enhancing several images.
The crystal structure of the proposed nitrogen-doped lutetium hydride phase. The hydrogens in octahedral interstitial sites are shown white and those in tetrahedral interstitial sites are pink. Lutetium atoms are green
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