Mechanism of Chalcophanite Nucleation in Zinc Hydroxide Sulfate Cathodes in Aqueous Zinc Batteries.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 37708460.
- Also identified by DOI 10.1021/acs.nanolett.3c02430.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Aqueous Zn-ion batteries with MnO<sub>2</sub>-based cathodes have seen significant attention owing to their high theoretical capacities, safety, and low cost; however, much debate remains regarding the reaction mechanism that dominates energy storage. In this work, we report our electron microscopy study of cathodes containing zinc hydroxide sulfate (Zn<sub>4</sub>SO<sub>4</sub>(OH)<sub>6</sub>·<i>x</i>H<sub>2</sub>O, ZHS) together with carbon nanotubes cycled in electrolytes containing ZnSO<sub>4</sub> with varied amounts of MnSO<sub>4</sub> incorporated. The primary Mn-containing phase is formed in situ in the cathode during cycling, where a dissolution-deposition reaction is identified between ZHS and chalcophanite (ZnMn<sub>3</sub>O<sub>7</sub>·3H<sub>2</sub>O). Mechanistic details of this reaction, in which the chalcophanite nucleates then separates from the ZHS flakes as the ZHS dissolves while acting as the primary Zn source for the reaction, are revealed using surface sensitive methods. These findings indicate the reaction is local to the ZHS flakes, providing new insight toward the importance of ZHS and the cathode microstructure.