Active sites for methanol synthesis on a Zn/Cu(100) catalyst

The active sites for methanol synthesis on a Zn/Cu(100) catalyst are clarified using the dipped adcluster model (DAM) combined with ab initio HF and MP2 calculations. In comparison with that on a Cu(100) catalyst studied previously, it is shown that the Cu–Zn site provides an easier reaction pathway for the rate-limiting step; the energy barriers are all lower and the dioxomethylene intermediate is more stable than that at the Cu–Cu site on a Cu(100) catalyst. The present results prove that the Cu–Zn site is the active site which cooperates with the Cu–Cu site to catalyze methanol synthesis. Electron transfer is the important factor in affecting the reactivity of the catalysts.