First-Principles Study of Honeycomb Borophene on the Mo2C Substrate

Honeycomb borophene (HB) is an important building block for diverse quantum phase observation and applications. However, freestanding HB is energetically unstable, resulting from electron deficiency. Based on a comprehensive first-principles study, we herein predict that the Mo2C monolayer can serve as an effective two-dimensional substrate to prepare planar HB. It is found that the planar HB layer is energetically favorable on the Mo2C substrate with desirable thermal and dynamical stabilities, benefiting from suitable interfacial interactions and electron transfer from Mo2C to HB. In addition, HB is found to be an effective buffer layer to decouple the electronic interactions and modify metal–semiconductor contact. These insightful results not only indicate that the Mo2C substrate is a promising alternative to synthesizing a stable borophene monolayer with pure honeycomb lattice but also provide hints for applications of HB-based materials in high-performance miniaturized electronic devices.