Recent Development of Mn‐based Oxides as Zinc‐Ion Battery Cathode

Abstract

Manganese‐based oxide is arguably one of the most well‐studied cathode materials for zinc‐ion battery (ZIB) due to its wide oxidation states, cost‐effectiveness, and matured synthesis process. As a result, there are numerous reports that show significant strides in the progress of Mn‐based oxides as ZIB cathode. However, ironically, due to the sheer number of Mn‐based oxides that have been published in recent years, there remain certain contemplations with regards to the electrochemical performance of each type of Mn‐based oxides and their performance comparison among various Mn polymorphs and oxidation states. Thus, to provide a clearer indication of the development of Mn‐based oxides, the recent progress in Mn‐based oxides as ZIB cathode was summarized systematically in this Review. More specifically, (1) the classification of Mn‐based oxides based on the oxidation states (i. e., MnO2, Mn3O4, Mn2O3, and MnO), (2) their respective polymorphs (i. e., α‐MnO2 and δ‐MnO2) as ZIB cathode, (3) the modification strategies commonly employed to enhance the performance, and (4) the effects of these modification strategies on the performance enhancement were reviewed. Lastly, perspectives and outlook of Mn‐based oxides as ZIB cathode were discussed at the end of this Review.

Construction of Bio‐inspired Film with Engineered Hydrophobicity to Boost Interfacial Reaction Kinetics of Aqueous Zinc–Ion Batteries

“…have been extensively employed as Zn 2+ host matrix owing to their open structure. [12][13][14][15] Despite these advances, the practical applications of AZIBs are still hindered by the intrinsic drawbacks of cathode materials, including sluggish reaction kinetics, drastic cathode dissolution, and inferior electronic conductivity. [8,11,16] Generally, these shortcomings are intimately associated with the aqueous electrolyte, which offers a suitable environment for the migration of Zn 2+ ions and dramatically affects the overall performance of the battery.…”

“…have been extensively employed as Zn 2+ host matrix owing to their open structure. [ 12–15 ] Despite these advances, the practical applications of AZIBs are still hindered by the intrinsic drawbacks of cathode materials, including sluggish reaction kinetics, drastic cathode dissolution, and inferior electronic conductivity. [ 8,11,16 ]…”

Iron‐Based NASICON‐Type Na4Fe3(PO4)2(P2O7) Cathode for Zinc‐Ion Battery: Zn2+/Na+ Co‐Intercalation Enabling High Capacity

“…However, ZIBs are still hindered by the lack of appropriate cathode materials which can tolerate the intercalation/deintercalation of divalent Zn 2+ [5–7] . To date, only a few categories, such as manganese‐based oxides, [8] vanadium‐based compounds, [9,10] Prussian blue analogues, [11,12] metal sulfide/oxides (VS 2 , MoS 2 , Co 3 O 4 ), [13–15] and organic compounds, [16,17] have been investigated as the cathode materials for ZIBs [18] . The NASICON (Na Super‐Ionic Conductor)‐structured cathode materials possess a 3D open framework with a high ionic conductivity and stable structure, which have been widely used in LIBs and sodium‐ion batteries (SIBs) [19,20] .…”

Recent Advances on Spinel Zinc Manganate Cathode Materials for Zinc‐Ion Batteries

“…Manganese has multiple valence states (+ 2, + 3, and + 4). [35] MnO 2 with a + 4-valence state can form different crystal structures (Figure 3c). This has aroused the interest of researchers.…”