Chemical vapor deposition of layered two-dimensional MoSi 2 N 4 materials

Stabilizing monolayer nitrides with silicon Transition metal carbides and nitrides are nonlayered materials that in monolayer form have potentially useful electronic and chemical properties. These monolayers are usually made by chemical etching that produces flakes with surface defects that have poor air and water stability. Hong et al. report that introducing silicon during chemical vapor deposition growth of molybdenum nitride passivates the surface and prevents island formation. Centimeter-scale monolayer films of the semiconductor MoSi 2 N 4 form as a MoN 2 layer sandwiched by two Si-N bilayers. These layers possess high mechanical strength and ambient stability. Science , this issue p. 670