DFT study of silicene on metal (Al, Ag, Au) substrates of various thicknesses

Highlights: • The silicene-based materials are promising for microelectronic applications. • Silicene on aluminum, silver and gold substrate becomes a conductive material. • The adhesion of silicene to metal substrates decreases in the sequence: Ag, Al, Au. • Al (111) substrate gives a uniform distribution of low normal stress in silicene. The silicene obtained on silver and gold substrates is not a subject for a large-scale use due to the high cost of the substrate materials. The aim of this work is to find a suitable low-cost substrate for the bulk production of silicene. In this work, three materials were investigated as a silicene substrate: Al, Ag, and Au. In all these cases, a metallic type of electronic conductivity was established in the silicene/substrate system. It turned out that the aluminum substrate provides an even better adhesion to silicene than the gold one. Silicene on the Al (111) substrate demonstrates the most uniform distribution of normal stresses with a minimum value of local bursts. Thus, aluminum seems to be quite a competitive material for the silicene production. The main obstacle in using aluminum substrates for the silicene production is strong oxidation in air.