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The paper focuses on theoretical and experimental aspects of an oxide surface optimization for oxygen reduction reaction (ORR). Various doped α-MnO 2 based electrocatalysts were prepared by microwave-assisted hydrothermal synthesis and electrochemically characterized to validate density functional theory (DFT) based predictions of the oxidation state and local structure effects on the catalytic activity of α-MnO 2 catalysts in ORR. Both theory and experiments conclude that the highest activity in ORR is to be expected in the case of clustered Mn 3+ sites which yield activity comparable with that of the polycrystalline Pt. These active sites have to be formed under in-operando conditions and their formation is hindered in doped α-MnO 2 catalysts. The activity of the other conceivable active sites based on non-clustered Mn 3+ or Mn 4+ is inferior to that of clustered Mn 3+ . The activation of Mn 3+ or Mn 4+ based active sites leads to a shift in selectivity of the ORR process towards 2 electron formation of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

• The DFT method is used to predict the complexing ability of GLY, PT and HEDP. • In the absence of H 2 O 2 , GLY has the strongest complexing capability. • In the presence of H 2 O 2 , HEDP has the strongest complexing capability. • PT is identified as the best candidate complexing agent for Co barrier CMP. Glycine (GLY), potassium tartrate (PT), and hydroxyethylidene diphosphonic acid (HEDP) have been used as effective complexing agents for chemical mechanical polishing (CMP) of a cobalt (Co) barrier layer, but the most suitable of these three complexing agents is still unclear. In this paper, the density functional theory (DFT) method is employed to predict the complexing capability of the three complexing agents to Co ions. The prediction results show that the complexing capability of the three complexing agents is in the order of: HEDP > GLY > PT. Then, electrochemical experiments, static corrosion tests, UV-Vis spectra, and XPS analysis successfully prove the effectiveness of the DFT method for molecular activity prediction. The experimental results show that regardless of the presence or absence of H 2 O 2 , PT has the weakest complexing capability, which results in sufficient Co removal rate without causing unnecessary Co dissolution. In addition, the complexation capability of HEDP is stronger than that of GLY when the oxidation of the Co surface is not a limiting factor. [Display omitted] [ABSTRACT FROM AUTHOR]