Mechanism of CH2 Steam Reforming on a Rh/ZrO2(111) Surface: A Computational Study

A periodic density-functional theory (DFT) calculation was performed to examine the steam-reforming reaction of CH2 on a Rh/ZrO2(111) surface. After loss of one hydrogen atom from H2O(a), OH(a) tends to associate with CH2(a) to form an intermediate, CH2OH(a), on the Rh cluster. This intermediate loses consecutive hydrogen atorns to form first CH2O(a) and then CHO(a), and ultimately produces CO(a) plus 4H((a)). The proposed overall reaction to produce gaseous CO and H-2 is calculated to be exothermic by 2.14 eV.