Effect of point defects on the properties of silicene-like BSi3 sheets from first-principles

• BSi3 sheets with Stone–Wales, vacancy and antisite defects have been studied.
• Compared to graphene or silicene, defect formation energies in BSi3 are smaller.
• Divacancies tend to lower their energies through structural reconstructions.
• Pristine and all of defected BSi3 sheets are planar, metallic and non-magnetic.

Density functional theory calculations are used to investigate the impact of point defects on BSi3 nanosheets. It is shown that the defects have low formation energies and are likely to form in BSi3 sheets. The divacancies with missing Si an B atoms are more probable than those which have two missing Si atoms and the diantisite (BSi)anti is also more probable than (BB)anti. It is found that the structural reconstructions caused by bond rotation in divacancies continuously lower the formation energies. Interestingly, unlike graphene or many other sheets, the presence of point defects does not change the planar structure and metallic behavior of BSi3 and all systems are nonmagnetic. The planar and metallic BSi3 sheets can therefore be used in devices, without any concern about the presence of defects.