Atomic scale onset of Al adhesion on Mo2BC

•Interfacial interactions between Mo2BC and an Al cluster were explored.•Al forms bonds to C constituting the onset of Al adhesion on Mo2BC.•These data are relevant for other carbide coatings.

We have explored interfacial interactions between a Mo–C terminated Mo2BC(040) surface and an Al cluster using ab initio molecular dynamics. The Al cluster is disrupted and wets the Mo2BC(040) surface. This can be understood based on the electronic structure. Across the Al–MoC interface C s–Al s hybridized states are formed. These bonds are stronger than the Al–Al intra-cluster bonds. Hence, the onset of Al adhesion is caused by bond formation across the Al–MoC interface.