A comparison of the NO–CO reaction over Rh(100), Rh(110) and Rh(111)

摘要: Reaction rates and product selectivities were measured over the Rh(100) surface as a function of temperature, CO NO partial pressures. These results are compared with our prior studies NO–CO reaction on Rh(111) Rh(110) surfaces. The only products detected for all three surfaces CO2, N2O, N2. Furthermore, we have found significant change in apparent activation energy (Ea) temperature. For it was that Ea can by factor 2.3 temperature range investigated here, from 528 to 700 K, lower values obtained at higher temperatures. In contrast, Ea's remain constant same observed suggest kinetics dominated variations coverages. At low temperatures, is fully saturated NO, dissociation limited availability vacancy sites through desorption. high still primarily covered however, number has increased substantially. this case, propose now reflecting rather than those