N2 emission in NO and N2O reduction on Rh(100) and Rh(110)
Abstract
The angular distribution of desorbing N2 was studied in both the thermal decomposition of N2O(a) on Rh(100) at 60–140 K and the steady-state NO (or N2O) + D2 reaction on Rh(100) and Rh(110) at 280–900 K. In the former, N2 desorption shows two peaks at around 85 and 110 K. At low N2O coverage, the desorption at 85 K collimates at about 66° off normal towards the [001] direction, whereas at high coverage, it sharply collimates along the surface normal. In the NO reduction on Rh(100), the N2 desorption preferentially collimates at around 71° off normal towards the [001] direction below about 700 K, whereas it collimates predominantly along the surface normal at higher temperatures. At lower temperatures, the surface