First-Principles Catalyst Design for Environmentally Benign Energy Production
EMSL Project ID
13299
Abstract
We are developing a first-principles approach to the design of novel catalytic materials. A fully parallelized planewave total energy Density Functional Theory (DFT)-based code is used for modeling elementary reaction steps on transition metal surfaces in order to design new catalysts based on first-principles calculations. In particular, the thermochemistry of reactions, atomic and molecular diffusion barriers, and activation energy barriers for chemical reactions are calculated with remarkable accuracy. Trends and discontinuities characterizing the behavior of metals across the periodic table can be clearly identified. These trends can be used as a guiding principle for the atomic-scale design of new catalysts, tailored to perform specific reactions with the desired activity and selectivity.The goal of this application is to request DOE supercomputing resources in order to study:
1. The mechanistic details of bond breaking and making in carbohydrates, and in particular simple alcohols, for the production of H2 vs alkanes from biomass products. Optimum catalyst compositions for an enhanced H2 selectivity should facilitate (a) C-C bond breaking and (b) the Water Gas Shift (WGS) reaction, whereas at the same time catalysts should inhibit the C-O bond breaking activity. In that respect, the detailed mechanism of the low temperature WGS reaction (CO+H2O --> CO2 + H2), leading to H2 production will be studied.
2. The detailed reaction mechanism for methanol (MeOH) decomposition on various transition metal surfaces based on Pt alloys. We expect to derive significant insight useful for designing new improved catalysts for: (a) the development of the next generation anode materials for Direct Methanol Fuel Cells (DMFCs), and (b) Hydrogen production from steam or aqueous phase MeOH reforming. The primary issues to be addressed in (a) is decreasing the materials cost of the Pt anode, and decreasing the CO poisoning effect at the Pt anode.
3. The detailed reaction paths for O2 reduction on monometallic and bimetallic single crystal surfaces. A major driving force for this project is the design of a better catalyst for the cathode of several types of low temperature FCs, using oxygen as the oxidant. Typical FC cathodes are made of Pt, which is very expensive. Our goal is to investigate the effect of alloying on Pt's reactivity towards oxygen. Hopefully, we can design Pt-alloys with decreased Pt loading and increased reactivity, meaning cheaper and more efficient FCs.
4. The fundamentals of Fischer-Tropsch synthesis of liquid fuels from CO and H2 on Fe-based catalysts. The continuously increasing price of oil makes the use of natural gas, the source of CO+H2, imperative and technologically very relevant. Yet, there is no quantum mechanical understanding of this important reaction mechanism so far.
5. The thermochemistry and kinetics of hydrogen interaction with transition metals and their alloys. This is becoming an increasingly important field, as we are moving towards the hydrogen economy. Issues addressed will be mostly relevant to hydrogen storage and to the use of hydrogen for catalytic applications.
Project Details
Project type
Exploratory Research
Start Date
2005-02-01
End Date
2005-12-15
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members