“…In order to further improve the performance of molybdenum carbide catalysts it is of value to understand the reactivity, selectivity, and stability of molybdenum carbide under various conditions. Numerous theoretical studies have investigated the surface stability [38,39,40,41], adsorption energies [42,43,44,45,46,47,48,49,50,51,40,52], reaction energetics [53,54,46,55,52], and alkali-doping [40,50] on Mo 2 C. The most well-studied surface is the Mo 2 C(001) surface, and both orthorhombic and hexagonal close packed Mo 2 C have been investigated. The results have indicated that the non-polar (011) surface is the most stable regardless of carbon chemical potential, but that the surface energies are sufficiently close that all surfaces are expected to be present on nanoparticles [40,39].…”