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Electrochemical Adsorption of Cs+ Ions on H-Todorokite Nanorods.

ABSTRACT: In this work, manganese oxide with a 3 × 3 tunnel structure was synthesized. Mg-todorokite was treated with HNO3 to obtain H-todorokite, which was used as an electrode for adsorption of Cs+ from aqueous solution by an electrochemical reaction. H-todorokite was electrochemically reduced to lower oxidation state to enhance its negative charge and simultaneously increase the amount of cations because of the charge compensation. The Cs+ adsorption on H-todorokite was completed by a coupled electrochemical reaction (the redox reaction between Mn3+ and Mn4+) and an ion-exchange reaction between Cs+ and H+ ions. Cyclic voltammetry measurements at different pHs and Cs+ concentrations were performed. H-todorokite revealed high electrochemical adsorption capacity for Cs+ because of the high crystallinity and stability of the materials, which reached 6.0 mmol g-1 in 0.1 mol·L-1 Na2SO4 solution.

SUBMITTER: Zhang H

PROVIDER: S-EPMC6977079 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Electrochemical Adsorption of Cs+ Ions on H-Todorokite Nanorods.

Zhang Hanping H Zhu Jingyi J Ma Lei L Kang Liping L Hu Mancheng M Li Shuni S Chen Yu Y

ACS omega 20200106 2

In this work, manganese oxide with a 3 × 3 tunnel structure was synthesized. Mg-todorokite was treated with HNO3 to obtain H-todorokite, which was used as an electrode for adsorption of Cs+ from aqueous solution by an electrochemical reaction. H-todorokite was electrochemically reduced to lower oxidation state to enhance its negative charge and simultaneously increase the amount of cations because of the charge compensation. The Cs+ adsorption on H-todorokite was ...[more]

PMID: 31984262

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