Computational Screening of Highly Stable Semiconducting MXenes with Ultrahigh Carrier Mobilities for Optoelectronic Applications

Abstract

Two‐dimensional (2D) transition metal carbides and nitrides known as MXenes are a new family of 2D materials. Most of the previous studies mainly focus on the metallic MXenes, there are few studies on semiconducting MXenes. Based on first‐principles calculations within density functional theory, 480 ground‐state structures including 444 metals and 36 semiconductors have been screened from 2256 MXenes using the energy and electronic parameters as the descriptors. The bandgap, carrier mobility, and optical absorption of the semiconducting MXenes show a strong dependence on the surface functional groups. By tuning the surface functional groups, the bandgaps can be changed from 0.2 to 3 eV. Moreover, the semiconducting MXenes exhibit high carrier mobilities up to 104 cm2 v−1s−1 and high optical absorption coefficients (>105 cm−1). This work demonstrates that Sc‐based and Y‐based MXenes present high stability, moderate bandgaps, ultrahigh carrier mobility, and high optical absorption, which make them large potential for electronics, optoelectronics, and photocatalysts.