On the stability of the CO adsorption-induced and self-organized CuPt surface alloy

The stability of the recently discovered CO-induced and self-organized CuPt surface alloy was explored at near ambient pressures of O2 (200 mbar) at room temperature, in a CO + H2 mix (Ptot = 220 mbar, 4% CO) from room temperature to 573 K, as well as in a CO + H2O mix (Ptot = 17 mbar, 50% CO) from room temperature to 673 K. No indications of substantial changes in surface structure were observed under the latter conditions compared to CO alone whereas the O2 oxidation resulted in CO removal and the build-up of an ultrathin CuOx-film. However, the oxidized CO/CuPt surface alloy could be regenerated by reducing the CuOx in 100 mbar CO for 10 min at room temperature. The results show, amongst others, the stability of the CuPt surface alloy in various environments containing CO and how a novel coinage/Pt-group bimetallic surface alloy catalyst induced by CO adsorption can be reactivated before use in applications such as electrochemistry at ambient temperatures.