摘要
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(2×2)patterned PtTe_(2)monolayer with kagome lattice formed by the well-ordered Te vacancy(PtTe_(1.75))hosts large and tunable spin Hall conductivity(SHC)and excellent hydrogen evolution reaction(HER)activity.The unconventional nature relies on the A1@1b band representation of the highest valence band without spin–orbit coupling(SOC).The large SHC comes from the Rashba SOC in the noncentrosymmetric structure induced by the Te vacancy.Even though it has a metallic SOC band structure,theℤ_(2)invariant is well defined because of the existence of the direct bandgap and is computed to be nontrivial.The calculated SHC is as large as 1.25×10^(3)h/e(Ωcm)^(−1)at the Fermi level(EF).By tuning the chemical potential from EF−0.3 to EF+0.3 eV,it varies rapidly and monotonically from−1.2×10^(3)to 3.1×10^(3)h/e(Ωcm)^(−1)In addition,we also find that 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.
出处
《Research》
SCIE
EI
CSCD
2023年第3期651-657,共7页
研究（英文）
基金
the National Natural Science Foundation of China(grant no.12204138,no.11974395,no.12188101,no.52188101,and no.51725103)
the Strategic Priority Research Program of Chinese Academy of Sciences(grant no.XDB33000000),and the Center for Materials Genome。
