First-Principles Study of Honeycomb Borophene on the Mo2C Substrate

Honeycomb borophene (HB) is an important building block for diverse quantumphase observation and applications. However, freestanding HB is energetically unstable, resultingfrom electron deficiency. Based on a comprehensivefirst-principles study, we herein predict thatthe Mo2C monolayer can serve as an effective two-dimensional substrate to prepare planar HB. Itis found that the planar HB layer is energetically favorable on the Mo2C substrate with desirablethermal and dynamical stabilities, benefiting from suitable interfacial interactions and electrontransfer from Mo2C to HB. In addition, HB is found to be an effective buffer layer to decouple theelectronic interactions and modify metal-semiconductor contact. These insightful results notonly indicate that the Mo2C substrate is a promising alternative to synthesizing a stableborophene monolayer with pure honeycomb lattice but also provide hints for applications of HB-based materials in high-performance miniaturized electronic devices