  Bi2O2Se is an emerging semiconducting, air-stable layered material (Nat.
Nanotechnol. 2017, 12, 530; Nano Lett. 2017, 17, 3021), potentially exceeding
MoS2 and phosphorene in electron mobility and rivalling typical Van der Waals
stacked layered materials in the next-generation high-speed and low-power
electronics. Holding the promise of functional versatility, it is arousing
rapidly growing interest from various disciplines, including optoelectronics,
thermoelectronics and piezoelectronics. In this work, we comprehensively study
the electrical properties of the native point defects in Bi2O2Se, as an
essential step toward understanding the fundamentals of this material. The
defect landscapes dependent on both Fermi energy and the chemical potentials of
atomic constituents are investigated. Along with the bulk defect analysis, a
complementary inspection of the surface properties, within the simple context
of charge neutrality level model, elucidates the observed n-type
characteristics of Bi2O2Se based FETs. This work provides important guide to
engineer the defects of Bi2O2Se for desired properties, which is key to the
successful application of this emerging layered material.
