  Semiconductors simultaneously possessing high carrier mobility, moderate
bandgap, and ambient environment stability are so important for the modern
industry, and Si-based semiconducting materials can match well with the
previous silicon based electronic components. Thus, searching for such Si-based
semiconductors has been one hot project due to the lack of them nowadays. Here,
with the help of density functional theory, we found that the oxidized bilayer
silicene exhibits high carrier mobility with a moderate direct bandgap of 1.02
eV. The high carrier mobility is caused by the remaining of big pi bond, and
the moderate bandgap is opened by the saturation of dangling Si 3p bonds.
Originated from the formation of strong Si-O and Si-Si bonds, the sample
exhibits strong thermodynamic and dynamical stabilities. Our work indicates
that the oxidized bilayer silicene has many potential applications in modern
electronic fields.
