Electronic and transport properties of Ti3C2O2-based strain sensor: A DFT-NEGF study

MXenes used as strain sensing materials have recently roused extensive interest due to their two-dimensional structures and outstanding electric properties. However, theoretical analysis from a quantum perspective is relatively scarce, which may hinder the development of this emerging field. Based on density functional theory with non-equilibrium Green’s function, we explored the structure, electronic, and transport properties of Ti3C2O2 with and without biaxial strains. The Ti3C2O2 monolayer remained stable under 5% biaxial strain. The structures and electronic properties of Ti3C2O2 showed gradual evolutions tuned by strain. Moreover, we studied the intrinsic device properties by constructing two-probe devices. The current of the 5% biaxially strained device increased by about 80% compared with the unstrained device. Given the results mentioned earlier, the Ti3C2O2-based nanodevices have the prospect of being strain sensors.