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Electrocatalytic oxidation of water at a polyoxometalate nanoparticle modified gold electrode.

ABSTRACT: Spherical polyoxometalate nanoparticles, [HPMo]NPs, were synthesized from a very well known Keggin-type polyoxometalate [H₃PMo₁₂O₄₀] in the presence of sodium dodecyl sulphate (SDS) and polyvinyl pyrrolidine (PVP) in aqueous medium and characterized by UV-Vis spectroscopy and Transmission Electron Microscopy (TEM). The [HPMo]NPs were used to modify a gold working electrode and they were characterized by SEM, EDX, elemental mapping, cyclic voltammetry and electrochemical impedance spectroscopy and applied for the electrocatalytic oxidation of water in a phosphate buffer solution at neutral pH. The modified electrode showed excellent electrocatalytic activity towards oxidation of water at an impressively low overpotential ∼350 mV with a high current density of around 1.7 mA cm^-2, good stability under exhaustive electrolysis conditions and also showed long term stability.

SUBMITTER: Mahanta A

PROVIDER: S-EPMC9076066 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Electrocatalytic oxidation of water at a polyoxometalate nanoparticle modified gold electrode.

Mahanta Abhinandan A Barman Koushik K Jasimuddin Sk S

RSC advances 20191126 66

Spherical polyoxometalate nanoparticles, [HPMo]NPs, were synthesized from a very well known Keggin-type polyoxometalate [H3PMo12O40] in the presence of sodium dodecyl sulphate (SDS) and polyvinyl pyrrolidine (PVP) in aqueous medium and characterized by UV-Vis spectroscopy and Transmission Electron Microscopy (TEM). The [HPMo]NPs were used to modify a gold working electrode and they were characterized by SEM, EDX, elemental mapping, cyclic voltammetry and electroc ...[more]

PMID: 35540240

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