Stable Manganese‐Oxide Composites as Cathodes for Zn‐Ion Batteries: Interface Activation from In Situ Layer Electrochemical Deposition under 2 V

• DOI: 10.1002/admi.202101924
• Publication Date: 2022-01-15T10:54:46Z
• Authors: Inmaculada Álvare...; Paloma Almodóvar; David Agustín Gir...; Francisco Llopis; Benjamín Solsona; María Luisa López
• Keywords: Birnessite

Abstract A set of multiphase manganese‐oxide composite materials (Mn 2 O 3 @Mn 4 and Mn 5 8 ), a birnessite‐type K x MnO oxide are prepared evaluated as cathodes for Zn‐ion batteries. The species formed when the electrodes subjected to V in aqueous solutions MnSO ZnSO analyzed, suggesting an interphase activation leading enhancement electrochemical response. For first time, it is shown that Zn (SO )(OH) 6 .xH phase coats composite‐type charging stage, contributing extending lifetime electrode with layered birnessite structure shows long cycling life at low current densities (122 mAh g −1 30 mA after 50 cycles) good efficiencies (ca. 99%) 0.1 2+ electrolyte. In contrast, 0.5 m electrolyte, high values specific capacity delivered by cell higher rates, is, 150 600 . performance due synergistic effect two compounds forming composite. Thus, more than 100 cycles this displays 175 2150 /1