%0 Journal Article %T Silicene’s pervasive surface alloy on Ag(111): a scaffold for two-dimensional growth %+ Physics Department E20 %+ Diamond Light Source %+ Département de Chimie, École Normale Supérieure %+ Université Paris sciences et lettres (PSL) %+ Sorbonne Université (SU) %+ Centre National de la Recherche Scientifique (CNRS) %+ Imperial College London %+ Paul Scherrer Institute (PSI) %A Küchle, Johannes %A Baklanov, Aleksandr %A Seitsonen, Ari Paavo %A Ryan, Paul %A Feulner, Peter %A Pendem, Prashanth %A Lee, Tien-Lin %A Muntwiler, Matthias %A Schwarz, Martin %A Haag, Felix %A Barth, Johannes %A Auwärter, Willi %A Duncan, David %A Allegretti, Francesco %@ 2053-1583 %J 2D Materials %I IOP Publishing %V 9 %N 4 %P 045021 %8 2022-09-06 %D 2022 %R 10.1088/2053-1583/ac8a01 %Z Physics [physics]Journal articles %X Abstract Silicene, the two-dimensional (2D) allotrope of silicon, is a promising material for electronics. So far, the most direct synthesis strategy has been to grow it epitaxially on metal surfaces; however, the effect of the strong silicon-metal interaction on the structure and electronic properties of the metal-supported silicene is generally poorly understood. In this work, we consider the 4 × 4 -silicene monolayer (ML) grown on Ag(111), probably the most illustrious representative of the 2D silicon family, and show that our experimental results refute the common interpretation of this system as a simple buckled, honeycomb ML with a sharp interface to the Ag substrate. Instead, the presented analysis demonstrates the pervasive presence of a second silicon species, which we conclude to be a Si–Ag alloy stacked between the 2D silicene and the silver substrate and scaffolding the 2D silicene layer. These findings question the current structural understanding of the silicene/Ag(111) interface and may raise expectations of analogous alloy systems in the stabilization of other 2D materials grown epitaxially on metal surfaces. %G English %L cea-04076292 %U https://cea.hal.science/cea-04076292 %~ CEA %~ CNRS %~ SORBONNE-UNIVERSITE %~ SORBONNE-UNIV %~ SU-TI %~ ALLIANCE-SU