Synchrotron radiation photoemission spectroscopy study on the phenomenon of alloying during stanene growth

[Background] As a new type of two-dimensional material, stanene has received extensive attention, due to its predicted excellent properties. [Purpose] This study aims to explore interaction between stanene and substrate during its growth which is an important research topic. [Methods] First of all, stanene was successfully prepared on the Au (111) surface by molecular beam epitaxy. Then the surface states of the samples were characterized by in situ low energy electron diffraction (LEED) and synchrotron radiation photoemission spectroscopy (SR-PES) at different stages. [Results] The results of LEED measurements show that different surface reconstructions occur on the sample surface at different coverage during the growth. SR-PES results show that the Au 4f peak has 0.3 eV shift toward the higher binding energy, and the composition of stanene in the Sn 4d peak increases significantly. [Conclusions] Sn atoms strongly interact with Au (111) to form the alloy of Au₂Sn, and with the increase of growth thickness, stanene gradually forms and covers the alloy surface. (authors)