Abstract
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Exploring stable two-dimensional materials
with appropriate band gaps and high carrier mobility is
highly desirable due to the potential applications in
optoelectronic devices. Here, the electronic structures of
phosphorene on a Au(111) substrate are investigated by
scanning tunneling spectroscopy, angle-resolved photoemission
spectroscopy (ARPES), and density functional
theory (DFT) calculations. The substrate-induced phosphorene
superstructure gives a superlattice potential,
leading to a strong band folding effect of the sp band of
Au(111) on the band structure. The band gap could be clearly identified in the ARPES results after examining the folded sp
band. The value of the energy gap (∼1.1 eV) and the high charge carrier mobility comparable to that of black phosphorus,
which is engineered by the tensile strain, are revealed by the combination of ARPES results and DFT calculations.
Furthermore, the phosphorene layer on the Au(111) surface displays high surface inertness, leading to the absence of
multilayer phosphorene. All these results suggest that the phosphorene on Au(111) could be a promising candidate, not
only for fundamental research but also for nanoelectronic and optoelectronic applications