Strain-Induced Band Modulation, Work Function, and QTAIM Analysis of Surface O-Functionalized Ti2C MXene

摘要

Functionalized MXenes have wide applications in the fields of gas sensors, thermoelectric materials, and hydrogen storage. Strain-induced band engineering and the work function (WF) of Ti_(2)CO_(2) MXene are investigated theoretically. The calculations reveal that Ti_(2)CO_(2) MXenes are stable because of the negative E _(coh), and all the strains considered are within the elastic limit. For Ti_(2)CO_(2) MXene, strain-induced blue shift of the Ti d state results in the transformation from a semiconductor to a metal. At about 4%, Ti_(2)CO_(2) MXene transforms from an indirect band gap to a direct band gap. The decreased WF induced by the strain improves the power efficiency of Ti_(2)CO_(2) MXene.