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The present work investigates the catalytic activity of NaNbO 3 microcubes decorated with CeO 2 nanorods on carbon (1 %, 3 %, 5 %, and 10 % w/w) for H 2 O 2 electrogeneration. The crystalline phases and the morphology of the materials were identified with scanning electron microscopy, transmission electron microscopy, X‐ray diffraction and X-ray Photoelectronic spectroscopy. Contact angle measurements were performed to characterize the hydrophilicity of each material. The H 2 O 2 electrogeneration was assessed by oxygen reduction reaction using the rotating ring-disk electrode technique. Electrochemical characterization results shown an enhancement on the H 2 O 2 electrogeneration by NaNbO 3 @CeO 2 /C-based materials compared to what was obtained with pure Vulcan XC72. The 1 % NaNbO 3 @CeO 2 /C electrocatalyst presented the lower starting potential for the ORR and a 2.3 electron transfer, favoring the 2-electron mechanism and providing a higher H 2 O 2 electrogeneration rate. Also, the enhancement of oxygen-containing functional groups showed the potential to comprehensively tune properties and optimize active sites and, consequently, increases the H 2 O 2 electrogeneration. Density functional theory calculations indicated that NaNbO 3 and CeO 2 surfaces have a similar low theoretical overpotential for this reaction and that CeO 2 improves the catalyst facilitating the electron transfer. These results indicate that NaNbO 3 @CeO 2 /C-based electrocatalysts are promising materials for in situ H 2 O 2 electrogeneration. [Display omitted] • NaNbO 3 microcubes decorated with CeO 2 nanorods on carbon for H 2 O 2 electrogeneration. • 1% NaNbO 3 @CeO 2 /C favoring the 2-electron mechanism, H 2 O 2 electrogeneration. • The oxygen-containing functional groups increases the H 2 O 2 electrogeneration. • DFT calculations indicated that NaNbO 3 and CeO 2 facilitating the electron transfer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Density Functional Theory Studies of Oxygen Reduction Reaction. • Hydrogen Peroxide Generation on Graphene-Based Catalysts. • Studies of two-electron pathway of the oxygen reduction reaction. • Recent progress on computational calculations from the hydrogen peroxide generation. The two-electron pathway of the oxygen reduction reaction has been gaining attention from the scientific community due to its capability of forming radical hydroxyl. In addition, it is a promising way of removing emergent pollutants, like dyes, pharmaceuticals, hormones, pesticides, and endocrine disruptors from water bodies, a very serious problem that currently challenges scientists and grows at a global scale. Theoretical calculations have already guided, over the last decade, the development of better catalysts for the oxygen reduction reaction. However, this mechanism had usually been, until recently, taken as an unwanted process since the preferred route for energy generation and the main focus of these studies is the four-electron pathway. This review summarizes the recent progress on computational calculations from the hydrogen peroxide generation process point of view, specifically focused on carbon-based materials. [ABSTRACT FROM AUTHOR]