Theoretical calculation assisted materials screening of BiOX (X = F, Cl, Br, I) for electrochemical absorption of cesium ions.

The electrochemical switching ion exchange (ESIX) technique has been widely used for the separation and recovery of radioactive cesium ions (Cs) from wastewater. In this study, a series of BiOX (X = F, Cl, Br, I) materials were first evaluated for their absorption properties to Cs through density functional theory (DFT) calculations. The calculations predict that BiOBr has the best absorption performance among the four materials, BiOF, BiOCl, BiOBr, and BiOI, due to its high absorption energy and low ion migration energy barrier to Cs.

Theoretical and experimental investigations of BiOCl for electrochemical adsorption of cesium ions.

BiOCl was found to have excellent electrochemical adsorption properties for cesium ions (Cs) in electrochemically switched ion exchange (ESIX). In this work, BiOCl nanosheets were synthesized by a hydrothermal method and used for electrochemical adsorption of Cs. The experimental results showed that BiOCl exhibited higher electrochemical adsorption selectivity for Cs than Li and Na.

DFT calculations of the synergistic effect of λ-MnO/graphene composites for electrochemical adsorption of lithium ions.

Recently, the composite of spinel-type manganese oxide (λ-MnO)/graphene has drawn wide attention because of its good electrochemical adsorption selectivity for low concentrations of Li ions from lake brine or seawater to cope with the fast-rising demand of lithium resources. In this composite, the synergistic effect between the good selectivity of λ-MnO for Li ions and the excellent conductivity of graphene play an important role for the electrochemical adsorption of Li ions. In order to reveal the synergistic mechanism in the electronic conductivity, the ionic conductivity and the ion selectivity of the λ-MnO/graphene composite, density functional theory (DFT) calculations combined with electrochemical adsorption experiments were carried out.