Theoretical dissection of superconductivity in two-dimensional honeycomb borophene oxide B2O crystal with a high stability

Atomically thin borophene has recently been synthesized experimentally, significantly enriching the boron chemistry and broadening the family of two-dimensional (2D) materials. Recently, oxides of 2D materials have been widely investigated for next-generation electronic devices. Based on the first-principles calculations, we predict the existence of the superconductivity in honeycomb borophene oxide (B2O), which possesses a high stability and could be potentially prepared by intrinsically incorporating oxygen into the recently synthesized borophene. The mechanical, electronic, phonon properties, as well as electron-phonon coupling of metallic B2O monolayer, have been systematically scrutinized. Within the framework of the Bardeen-Cooper-Schrieffer theory framework, the B2O monolayer exhibits an intrinsic superconducting feature with a superconducting transition temperature (T-c) of similar to 10.3 K, higher than many 2D borides (0.2-7.8 K). Further, strain can be utilized to tune the superconductivity with the optimalT(c)of 14.7 K under a tensile strain of 1%. The superconducting trait mainly originates from the out-of-plane soft-mode vibrations of the system, which are significantly enhanced via the light O atoms' incorporation compared to other 2D metal-boride superconductors. This strategy would open a door to design 2D superconducting structures via the participation of light elements. We believe our findings greatly bloom the 2D superconducting family and pave the way for future nanoelectronics.