Adsorption of O 2 and C 2 H n ( n =2, 4, 6) on the Al 9 Co 2 (001) and o-Al 13 Co 4 (100) complex metallic alloy surfaces

•Oxidation mechanisms on Al9Co2(001) and Al13Co4(100) CMA surfaces.•Oxidation kinetics dependent on oxygen partial pressure; no aluminium segregation.•Lack of aluminium segregation ascribed to strong covalent bonds within the crystals.•Competition between oxide film growth or dissolution, O2 desorption or dissolution.•C2Hn (n=2, 4, 6) not adsorbed on Al13Co4(100).