Microkinetics of steam methane reforming on platinum and rhodium metal surfaces

► Elementary reaction steps of SMR for Pt(111), Pt(533) and Pt(210) calculated by DFT. ► The rate-controlling step is dissociative methane adsorption. ► Rhodium is more active than platinum in methane steam reforming. ► The reaction mechanism toward CO depends on metal and surface topology. ►An alcoholate intermediate is implicated for Pt(210) in contrast to Rh(211).