Peeling Silicene From Model Silver Substrates in Molecular Dynamics Simulations

Silicene is a two-dimensional (2D) allotrope of silicon with a rippled or corrugated honeycomb structure in analogy to graphene. Its semiconducting properties make it attractive for developing future nano-electronic devices. However, it has been challenging to obtain its naked form by using a mechanical exfoliation method as what has been applied to graphene. Here, we use fully atomistic simulations with an effective potential for the silver substrate derived from first-principles calculations to investigate possible ways of peeling silicene solely by mechanical force. We find that the peeling direction is critical for exfoliating silicene and the peeling at a 45 deg angle with the substrate is the most efficient one to detach silicene. Our study could help to understand the mechanics of silicene on substrates and guide the technology of isolation of silicene from the substrate on which it is synthesized.