In Situ N-Doped Graphene and Mo Nanoribbon Formation from Mo₂ Ti₂ C₃ MXene Monolayers

Since the advent of monolayered 2D transition metal carbide and nitrides (MXenes) in 2011, the number of different monolayer systems and the study thereof have been on the rise. Mo₂ Ti₂ C₃ is one of the least studied MXenes and new insights to this material are of value to the field. Here, the stability of Mo₂ Ti₂ C₃ under electron irradiation is investigated. A transmission electron microscope (TEM) is used to study the structural and elemental changes in situ. It is found that Mo₂ Ti₂ C₃ is reasonably stable for the first 2 min of irradiation. However, structural changes occur thereafter, which trigger increasingly rapid and significant rearrangement. This results in the formation of pores and two new nanomaterials, namely, N-doped graphene membranes and Mo nanoribbons. The study provides insight into the stability of Mo₂ Ti₂ C₃ monolayers against electron irradiation, which will allow for reliable future study of the material using TEM. Furthermore, these findings will facilitate further research in the rapidly growing field of electron beam driven chemistry and engineering of nanomaterials.