N-doped carbon materials are considered as next-generation oxygen reduction reaction (ORR) catalysts for fuel cells due to their prolonged stability and low cost. However, the underlying mechanism of these catalysts has been only insufficiently identified, preventing the rational design of high-performing catalysts. Here, we show that the first electron is transferred into O2 molecules at the outer Helmholtz plane (ET-OHP) over a long range. This is in sharp contrast to the conventional belief that O2 adsorption must precede the ET step and thus that the active site must possess as good an O2 binding character as that which occurs on metallic catalysts. Based on the ET-OHP mechanism, the location of the electrode potential dominantly characterizes the ORR activity. Accordingly, we demonstrate that the electrode potential can be elevated by reducing the graphene size and/or including metal impurities, thereby enhancing the ORR activity, which can be transferred into single-cell operations with superior stability.

Long range electron transfer over graphene-based catalyst for high performing oxygen reduction reactions: Importance of size, N-doping, and metallic impurities

Low energy SUSY confronted with new measurements of W-boson mass and muon g-2.

Manganese-incorporated Co3O4 catalysts were prepared via thermal pyrolysis of ZIF-67, and the effect of manganese incorporation and annealing temperature on their catalytic performances for oxygen reduction and evolution reactions (ORR, OER) were investigated. Notable crystalline distortion was induced by manganese insertion into Co3O4 lattice, resulting in smaller crystallite size, more abundant Co2+ and considerable oxygen vacancies. All these properties were regarded as the crucial origins for electrocatalytic activity elevation. The catalyst annealed at 450 °C (denoted as Mn/Co-450) exhibited the optimal catalytic activity with an ultra-low potential gap (0.83 V). Using Mn/Co-450 as an air cathode, the zinc-air battery delivered high power density (115.5 mW cm−2), competitive specific capacity (783.4 mAh g−1) and good cycling stability. The theoretical overpotentials of ORR and OER were respectively decreased by 0.18 V and 0.05 V by DFT calculation due to the weakened interaction between Co and OH group and the strengthened Co-OOH interaction. 

Mn-incorporated Co3O4 bifunctional electrocatalysts for zinc-air battery application: An experimental and DFT study

Recent developments of Co<sub>3</sub>O<sub>4</sub>-based materials as catalysts for the oxygen evolution reaction

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Papers

Immunomodulatory microneedle patch for periodontal tissue regeneration

Co/Co3O4 nanoparticles embedded into thin O-doped graphitic layer as bifunctional oxygen electrocatalysts for Zn-air batteries

Co/Co3O4 nanoparticles embedded into thin O-doped graphitic layer as bifunctional oxygen electrocatalysts for Zn-air batteries

Co3O4@TiO2@Y2O3 nanocomposites for a highly sensitive CO gas sensor and quantitative analysis.

Co3O4@TiO2@Y2O3 nanocomposites for a highly sensitive CO gas sensor and quantitative analysis