Prediction of high-temperature ambient-pressure superconductivity in hexagonal boron-rich clathrates

Abstract

Inspired by recent predictions of superconductivity in B-C framework clathrates, we employ density functional theory to explore potential superconductors among hexagonal hydride-substituted compounds with compositions XB${}_8$C, XB${}_7$C${}_2$, XB${}_6$C${}_3$, XB${}_3$C${}_6$, XB${}_2$C${}_7$, and XBC${}_8$. Our high-throughput calculations on 96 compounds reveal several dynamically stable candidates exhibiting superconductivity at ambient pressure. Analysis of electronic structures and electron-phonon coupling demonstrates that CaB${}_8$C, SrB${}_8$C, and BaB${}_8$C possess superconducting transition temperatures ($T_c$) exceeding 50 K, with CaB${}_8$C exhibiting the highest predicted $T_c$ of 77.1 K among all stable compounds studied. These findings expand the family of B-C clathrate superconductors and provide valuable insights for experimental efforts aimed at discovering novel superconducting materials.

References in corpus (23)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Conventional superconductivity at 203 K at high pressures
• Quantum ESPRESSO toward the exascale
• Superconductivity at 250 K in lanthanum hydride under high pressures
• Superconductivity in diamond
• Synthesis of clathrate cerium superhydride CeH9 below 100 GPa with atomic hydrogen sublattice
• Superconductive "sodalite"-like clathrate calcium hydride at high pressures
• Precision and efficiency in solid-state pseudopotential calculations
• Superconductivity of bulk CaC6
• Anharmonic free energies and phonon dispersions from the stochastic self-consistent harmonic approximation: application to platinum and palladium hydrides
• FermiSurfer: Fermi-surface viewer providing multiple representation schemes
• Superconductivity at 253 K in lanthanum-yttrium ternary hydrides
• First-Principles Theory of Anharmonicity and the Inverse Isotope Effect in Superconducting Palladium-Hydride Compounds
• The Stochastic Self-Consistent Harmonic Approximation: Calculating Vibrational Properties of Materials with Full Quantum and Anharmonic Effects
• LaBH${}_8$: the first high-T${}_c$ low-pressure superhydride
• Second order structural phase transitions, free energy curvature, and temperature-dependent anharmonic phonons in the self-consistent harmonic approximation: theory and stochastic implementation
• Improved tetrahedron method for the Brillouin-zone integration applicable to response functions
• Conventional high-temperature superconductivity in metallic, covalently bonded, binary-guest C-B clathrates
• Superconductivity in CeBeH${}_8$ and CeBH${}_8$ at moderate pressures
• Machine learning guided discovery of superconducting calcium borocarbides
• Superconductivity near 70 K in boron-carbon clathrates MB${}_2$C${}_8$ (M = Na, K, Rb, Cs) at ambient pressure
• Properties of B4C in the shocked state for pressures up to 1.5 TPa
• Ca-intercalated graphite as a hydrogen storage material: stability against decomposition into calcium hydride and graphite

Cited by in corpus (1)

• HTSC-2025: A Benchmark Dataset of Ambient-Pressure High-Temperature Superconductors for AI-Driven Critical Temperature Prediction