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Annual report on PRF48797-ND6 The New Direction grant is aimed at the elucidation of the mechanism of methanol steam reforming (MSR) using the planewave density functional theory (DFT). In the previous funding year, much progress has been made. In the first project, we have carried out extensive DFT calculations on the initial steps of MSR on PdZn and ZnO surfaces, which involve the cleavage of the O-H bond in both CH3OH and H2O. The results have been written up for publication on J. Phys. Chem. C, and the manuscript is in the final stages of being accepted for publication.1 Our calculations indicated that the dissociative adsorption processes of both CH3OH and H2O on PdZn surfaces are highly activated, although defect sites significantly lower the activation barriers. We have also found that the dissociation become much more facile on the ZnO(0001) surface. This observation led us to conclude that the catalyst support (ZnO) might play an important role in MSR. In the second project, we have performed extensive calculations on methanol decomposition on Pd surfaces. This project is designed to understand the differences between the Pd and PdZn surfaces. Our findings indicated that the decomposition of CH3OH follows a different pathway that involves the C-H bond cleavage. We are in the process of developing a kinetic Monte Carlo model to simulate this catalytic process. In the third project, we are exploring the selectivity of the Cu catalyst for MSR. The exclusive production of CO2 on the Cu catalyst might involve reactions between adsorbed formaldehyde (H2CO) and OH, produced from dehydrogenation of CH3OH and H2O. Our results indicated that the formal radical is probably not involved as it decays to CO readily with a small barrier. We are focus on the substitution reaction H2CO(ad) + OH(ad) --> H(ad) + OCHOH(ad), whose product yields CO2 after dehydrogenation. This and other related reactions might provide important insights into the MSR mechanism. (1) Smith, G. K.; Lin, S.; Lai, W.; Datye, A. K.; Xie, D.; Guo, H. J. Phys. Chem. C to be published.