In this work, we present a novel methodology to transform the metal monochalcogenide (MMC) β-SnSe into the surface alloy Au2Sn through exposure to atomic hydrogen, which promotes selenium desorption from the surface. We have charactertized the transformation by means of STM, XPS and LEED, identifying an intermediate state where both phases coexist, prior to the complete conversion into the alloy. In addition, theoreticals calculations shed light on the underlying mechanisms, indicating that selenium leaves the surface in the form of H2Se. We believe that this approach may be generalized to other 2D MMC and surface alloys.
This work has been published in:
«Hydrogen-driven transition from a 2D-metal monochalchogenide to a surface alloy», S. Jimenez-Fernandez, E. Tosi, J. I. Martinez, V. Villalobos-Vilda, J. A. Martin-Gago, C. Sanchez-Sanchez, I. Palacio, Surf. Interfaces 80 (2026) 108321. Link