Manipulation of electronic and magnetic properties of Cr2CX2 (X=F,O,OH) monolayer by applying mechanical strains

Abstract

Adjusting the electronic and magnetic properties of materials by strain engineering is an effective strategy to improve the performance of electronic and spin electronic devices. In this paper, we study the electronic and magnetic properties of Cr2C and Cr2CX2 (X = F, O,OH) under mechanical strain based on density functional theory. In the strain-free state, Cr2C and Cr2CO2 are in the ferromagnetic (FM) metallic ground states, while Cr2CF2 and Cr2C(OH)2 are in the antiferromagnetic (AFM) semiconducting states. Applying tensile strain can enhance the magnetic moments of the Cr atoms of all the Cr2C and Cr2CX2 (X = F, O, OH) systems. The electronic structure can also be affected with the increase of strain, e.g., resulting in narrowing of the band gap of the AFM semiconducting systems (Cr2CF2 and Cr2C(OH)2) and enhancing the spin-splitting of the FM metallic systems (Cr2C and Cr2CO2). The results indicate a possible broadened applicability of strained Cr2C-based MXenes in future spintronics.