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 (P_tot = 220 mbar, 4% CO) from room temperature to 573 K, as well as in a CO + H₂O mix (P_tot = 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 CuO_x-film. However, the oxidized CO/CuPt surface alloy could be regenerated by reducing the CuO_x 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.