Large spin Hall conductivity and excellent hydrogen evolution reaction activity in unconventional PtTe1.75 monolayer

Abstract

Two-dimensional (2D) materials have gained lots of attention due to the potential applications. In this work, we propose that based on first-principles calculations, the (2$\times$2) patterned PtTe${}_2$ monolayer with kagome lattice formed by the well-ordered Te vacancy (PtTe${}_{1.75}$) hosts large spin Hall conductivity (SHC) and excellent hydrogen evolution reaction (HER) activity. The unconventional nature relies on the $A1@1b$ band representation (BR) of the highest valence band without SOC. The large SHC comes from the Rashba spin-orbit coupling (SOC) in the noncentrosymmetric structure induced by the Te vacancy. Even though it has a metallic SOC band structure, the ${\mathbb{Z}}_2$ invariant is well defined due to the existence of the direct band gap and is computed to be nontrivial. The calculated SHC is as large as 1.25$\times 10^3\frac{\hslash }{e}(\Omega cm{)}^{-1}$ at the Fermi level ($E_F$). By tuning the chemical potential from $E_F-0.3$ to $E_F+0.3$ eV, it varies rapidly and monotonically from $-1.2\times 10^3$ to 3.1$\times 10^3\frac{\hslash }{e}(\Omega cm{)}^{-1}$. In addition, we also find the Te vacancy in the patterned monolayer can induce excellent HER activity. Our results not only offer a new idea to search 2D materials with large SHC, i.e., by introducing inversion-symmetry breaking vacancies in large SOC systems, but also provide a feasible system with tunable SHC (by applying gate voltage) and excellent HER activity.

References in corpus (31)

• Quantum Spin Hall Effect in Graphene
• $Z_2$ Topological Order and the Quantum Spin Hall Effect
• Berry Phase Effects on Electronic Properties
• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• Weyl and Dirac Semimetals in Three Dimensional Solids
• Maximally localized Wannier functions: Theory and applications
• WannierTools: An open-source software package for novel topological materials
• Three Dimensional Dirac Semimetal and Quantum Transports in Cd3As2
• Topological quantum chemistry
• Beyond Dirac and Weyl fermions: Unconventional quasiparticles in conventional crystals
• Giant Spin-splitting in the Bi/Ag(111) Surface Alloy
• Lorentz-violating type-II Dirac fermions in transition metal dichalcogenide PtTe${}_2$
• Irvsp: to obtain irreducible representations of electronic states in the VASP
• Double Dirac Semimetals in Three Dimensions
• Strong, anisotropic anomalous Hall effect and spin Hall effect in chiral antiferromagnetic compounds Mn${}_{3}X$ ($X$ = Ge, Sn, Ga, Ir, Rh and Pt)
• A Charge-Density-Wave Topological Semimetal
• Magnetic semimetals and quantized anomalous Hall effect in EuB6
• Low-Temperature Eutectic Synthesis of PtTe2 with Weak Antilocalization and Controlled Layer Thinning
• Unconventional Materials: the mismatch between electronic charge centers and atomic positions
• Crossover from 2D metal to 3D Dirac semimetal in metallic PtTe2 films with local Rashba effect
• Topological phases in the TaSe3 compound
• Approaching the Type-II Dirac Point and Concomitant Superconductivity in Pt-doping Stabilized Metastable 1T-phase IrTe2
• Application of topological quantum chemistry in electrides
• Six-fold Excitations in Electrides
• Quantum Spin Hall Effect in Ta${}_2$M${}_3$Te${}_5$ (M = Pd, Ni)
• Observation of quantum spin Hall states in Ta${}_2$Pd${}_3$Te${}_5$
• High-throughput screening for Weyl Semimetals with S${}_4$ Symmetry
• Topological insulators in the NaCaBi family with large SOC gaps
• Weyl Semimetals with $S_4$ symmetry
• Twisted nodal wires and three-dimensional quantum spin Hall effect in distorted square-net compounds
• Epitaxial Growth of Monolayer PdTe2 and Patterned PtTe2 by Direct Tellurization of Pd and Pt surfaces

Cited by in corpus (5)

• Evidence for Two-dimensional Weyl Fermions in Air-Stable Monolayer PtTe${}_{1.75}$
• Majorana corner modes in unconventional monolayers of the 1T-PtSe2 family
• Unconventional phonon spectra and obstructed edge phonon modes
• Hinge Majorana Flat Band in Type-II Dirac Semimetals
• Impact of the out-of-plane conductivity on spin transport evaluation in a van der Waals material