Anomalous layer-dependent electronic and piezoelectric properties of 2D GaInS3 nanosheets

Two-dimensional (2D) GaInS3 nanosheets are found to exhibit thermal and structural stabilities, good oxidation resistance, and tunable and layer-dependent electronic properties from first-principles calculations. Remarkably, the nanosheets with arbitrary thickness possess robust in-plane piezoelectricity without the odd-even effect commonly observed in other 2D piezoelectric materials, which is attributed to the retention of noncentrosymmetry resulting from their homogeneous and direct stacking patterns. The piezoelectric stress coefficient e113D of the nanosheets is about 0.23 C/m2, almost independent of the numbers of atomic layers of 2D GaInS3. The stability in piezoelectricity and the high carrier mobility of 2D GaInS3 nanosheets could endow them with promising application prospects in nanoelectronic and nanoelectromechanical devices.