2021/08/20 by P. P. Kong, Vasily S. Minkov, Mikhail A. Kuzovnikov +10 · 12 citations
Earth and Planetary Sciences · Materials Science · Physics and Astronomy · #High-pressure geophysics and materials #Nuclear Materials and Properties #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.1038/s41467-021-25372-2
openalex publication_date 2021/08/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/27
Abstract The discovery of superconducting H 3 S with a critical temperature T c ∼200 K opened a door to room temperature superconductivity and stimulated further extensive studies of hydrogen-rich compounds stabilized by high pressure. Here, we report a comprehensive study of the yttrium-hydrogen system with the highest predicted T c s among binary compounds and discuss the contradictions between different theoretical calculations and experimental data. We synthesized yttrium hydrides with the compositions of YH 3 , YH 4 , YH 6 and YH 9 in a diamond anvil cell and studied their crystal structures, electrical and magnetic transport properties, and isotopic effects. We found superconductivity in the Im-3m YH 6 and P6 3 /mmc YH 9 phases with maximal T c s of ∼220 K at 183 GPa and ∼243 K at 201 GPa, respectively. Fm-3m YH 10 with the highest predicted T c > 300 K was not observed in our experiments, and instead, YH 9 was found to be the hydrogen-richest yttrium hydride in the studied pressure and temperature range up to record 410 GPa and 2250 K.