Tuning the electric transport behavior of AgCrSe 2 by intrinsic defects

The two-dimensional (2D) structure often leads to unusual phenomena for the impact of confined mean free path of carrier scattering. As a quasi-2D layered material, AgCrSe 2 has a liquid-like phonon behavior for its unstable Ag atoms at service temperature, leading to the promising candidate for thermoelectricity and fast ionic conductor. However, the inferior electronic performance constrains its application prospects as a functional semiconductor, which provides broad opportunity to tune its electric behaviors by defect chemistry. In this work, we revealed abundant electric transport behaviors of AgCrSe 2 with different types of intrinsic defects. For example, the AgCrSe 2 changes from Anderson insulator to metal when Se defects become prevailing and the magnetoresistance alters its sign depending on the relative ratio of Ag and Cr defects. Our results reported here can give salutary boosting on regulating the electric properties of ternary transition metal selenide by defect chemistry.