Automobile exhaust emmissions have been among the primary sources of air pollution in most major cities for the few decades. In an effort to decrease air pollutants from car exhausts, substantial research has been done on catalytic reduction of NO by CO. Current state-of-the-art solid state physics methods, such as Density Functional Theory (DFT) calculations allow for the accurate and detailed characterization of heats of reactions and activation energy barriers. The main objective of the proposed project is to implement DFT slab-type calculations to explore some of the critical mechanistic details of the NO+CO reaction over the most commonly used Pt-Rh catalyst. ] the adsorption and dissociation of NO on (1) pure Pt, (2) pure Rh single crystal surfaces and (3) different compositions of a bimetallic Pt-Rh surface alloy will be investigated. Similar work is proposed for CO.
permitting, the above elementary reaction steps over other interesting metals (Ir, Pd) and alloys (Au-Rh, Au-Pt) be investigated. Such alloys are expected to allow fine-tuning of catalyst activity and selectivity. The ultimate goal to identify the mechanistic trends for the NO+CO reaction over different surfaces and propose a good candidate replacing the current catalyst, suffering from the fast decline of Rh natural reserves. Training content (objective, benefit and expected impact): The completion of the research project proposed would guarantee the multifaceted training of the applicant the area of DFT methods as applied to the prediction of solids' properties and chemical reactivity of surfaces. These methods have already been proven to treat the central problem of catalysis, namely chemisorption, with remarkable accuracy. The applicant will gain an active knowledge of DFT methods during the course of this project, allowing him to embark on his own research career in theoretical surface science and catalysis.
The detailed understanding of critical elementary reaction steps for the NO+CO reaction over several m and alloys will certainly provide substantial insight and suggest directions for designing a catalyst with high act and selectivity. The potential impact in automotive industry and through that to the improvement of the global environment cannot be underestimated
Links with industry / industrial relevance (22):
Members of CAMP-DTU have developed strong research ties with Haldor Topsoe A/S, one of the D European industrial companies heavily involved with R&D of catalytic processes.