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The supported catalysts have received great attentions due to their high catalytic activity, low cost and good stability. Here we report the stability, wetting ability, corrosion resistance and catalytic activity of the supported catalysts with group 9, 10 and 11 metals (M = Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au) monolayers (ML) deposited on NbC(001), denoted as M ML /NbC(001). The Pd ML /NbC(001) and Pt ML /NbC(001) are testified as the most stable and active ones with the former even better on the whole. The catalytic activities toward oxygen reduction reactions (ORR) are clarified by the dissociation and the change in Gibbs free energies for the elementary reaction steps of O 2 on Pd ML /NbC(001). [ABSTRACT FROM AUTHOR]

Using the first principles methods, the geometric and electronic structures of the metal monolayers supported on WC(0001) surfaces (M ML /WC(0001) (M = Pt, Pd, and Au)) and their catalytic activity toward the oxygen reduction reaction (ORR) were comparatively studied. Both the kinetics and the density of states results demonstrated that the direct dissociation of O 2 on all three M ML /WC(0001) surfaces are almost impossible. Yet the barriers of the formation and dissociation of OOH on Au ML /WC(0001) are much smaller than those on the Pt ML /WC(0001) and the Pd ML /WC(0001) surfaces, implying that the Au ML /WC(0001) exhibits the highest catalytic activity for ORR via a combination of 2e − hydrogenation of O 2 and 4e − dissociation of OOH. The rate-limiting step barrier of 0.83 eV for the hydrogenation of OH forming H 2 O is also comparable to that on the traditional Pt-based catalysts. The deactivation mechanism of Pt ML /WC(0001) and the performance of Pd ML /WC(0001) for ORR were identified. The present study is conductive to designing new efficient catalyst without using of the precious Pt for efficiently promoting ORR. [ABSTRACT FROM AUTHOR]

The mechanisms for oxygen reduction reaction (ORR) on the metal-free phosphorus doped graphene (P-Gra) support are investigated using the density function theory (DFT) calculations. It is found that all the ORR species can be strongly adsorbed on the P-Gra except for the H 2 O molecule. Our calculation results show that all of the possible ORR elementary reactions could take place within a small region around the dopant and the ORR could proceed firstly by a 2e − process to form an OOH intermediate, which is followed by the 4e − process to break the O–O bond of OOH. Along this reaction path, the reduction of the second OH to H 2 O is the rate-limiting step with the largest barrier of 0.88 eV. To the best of our knowledge, this is the first theoretical investigation on the mechanisms for the entire process of the ORR on the P-Gra. [ABSTRACT FROM AUTHOR]