To shed light on the effect of the alloy concentration over the time evolution of CO 2 production, the DFT calculations were complemented with an 8-step microkinetic model, following the approach of previous work. Microkinetic modeling allows us to make a more direct comparison between DFT calculations and experimental variables such as partial pressures and temperatures. Importantly, the coverage effects are also considered, offering a thorough assessment of the catalyst poisoning tendency. In the simulations reported herein, the temperature was varied from 100 to 500 K and the O 2 :CO ratio of the feed was altered to simulate different environments (viz., P O2 = 0.5 bar, P CO = 0.5 bar; P O2 = 0.5 bar, P CO = 0.05 bar; P O2 = 0.05 bar, P CO = 0.5 bar). It should be stressed that no a priori assumptions were made about the rate-determining step or steady-state surface coverages. The elementary steps and reactor model are described in greater detail in the SI.