Phase diagrams of the terminating oxygen layer on MXenes M2CO sheets (M = Ti, V, Nb)

Abstract

Abstract In this work we have studied the behavior of oxygen adsorbed on the MXenes M2CO (M=Ti, V, Nb) surface by the density functional theory and Monte Carlo methods. An approximation for the lateral interactions potential has been constructed that has the form of a pair potential. We have carried out the quantitative assessment of the errors of the pair potential. Using SuSMoST program we have constructed isotherms of adsorption. The results showed a non-trivial phase behavior of the adlayer: we observed three phases characterized by the 1/3, 1/2 and 2/3 coverage. It has been predicted that complete oxygen removal from the MXenes surface is possible at temperatures above 500 K.