Understanding the Mechanism of deNOx on Rh, Pd and Pt Surfaces
Lead PI:Prof. Graeme Watson
Abstract:Nitrogen oxide based emissions from combustion engines have become a topic of concern in recent years, due to the harmful effects they have on the environment. Decomposition of NOx (x = 1,2) (deNOx) leads to the emissions of N2O and NO2 which damage the ozone layer. As a result, strict regulations have been imposed on NOx (x = 1, 2) emissions, leading to the development of three way car catalysts (TWC). The active metals used in TWC’s are Rh, Pd and Pt. Extensive research has shown that Rh is a more effective active metal at deNOx, however it is rare and expensive. Furthermore, research into the mechanism of deNOx on the active support metals in TWC’s, to fully understand the reduction of NOx emissions to nitrogen and oxygen gas is in heated debate. Hence, elucidation of the mechanism on Rh, Pd and Pt active metal surfaces will help to understand the decomposition process and develop new low-cost metal catalysts to fully reduce nitrogen based emissions. We will explore adsorption of O, NO and NO2 on the low index surfaces of Rh, Pd and Pt using DFT: GGA calculations as the first step in understanding the mechanism of the NO and NO2 decomposition processes.