Electro‐catalytic oxidation of hydroxide ion by Co3O4 and Co3O4@SiO2 nanoparticles both at particle ensembles and single particle level

Journal article

We report that the Co 3 O 4 nanoparticle‐mediated electrochemical oxidation under alkaline conditions of hydroxide ion on a glassy carbon macroelectrode leads to hydrogen peroxide as the initial oxidation product of electron transfer. The latter is inferred to subsequently partially decompose to dioxygen by catalytic chemical reaction at the nanoparticles. At the single particle level, electrochemical particle‐electrode impacts point out the rate‐determining step and the limiting kinetics of the reaction. Further, particles with core‐shell structure of a Co 3 O 4 core and SiO 2 shell are synthesised, and their electrochemical behaviour is studied and compared with bare Co 3 O 4 nanoparticles, suggesting the very likely broken or highly porous state of the silica shell, which is not otherwise easily distinguished, for example by electron microscopy.

Authors: Xie, R-C; Volokhova, M; Boldin, A; Seinberg, L; Tsujimoto, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wiley
• Journal: ChemElectroChem
• Volume: 7
• Issue: 5
• Pages: 1261-1276
• Publication date: 2020-03-11
• Acceptance date: 2020-02-26
• DOI: 10.1002/celc.202000230
• EISSN: 2196-0216
• Language: English
• Keywords: nano-impacts; cobalt (II) dicobalt (III) oxide nanoparticles; FFR; hydroxide ion oxidation; electrocatalysis; core-shell nanoparticles