Electrochemically Induced Defects Promotional High-Performance Binder-Free MnO@CC Cathodes for Flexible Quasi-Solid-State Zinc-Ion Battery

Abstract

Aqueous Zn-ion batteries (ZIBs) have attracted ever-increasing attention because of their features of a cheaper cost, high safety level, and environment protection. Manganesebased oxides stand out among the many cathode material candidates because of their high voltage platform (1.4 V vs Zn 2+ /Zn). Nevertheless, manganese ion dissolution still is an essential issue in the application of manganese-based cathodes, and the strategy of using manganese ion dissolution to activate electrode materials is rarely achieved. Here, a high-capacity and stable binder-free MnO@CC cathode was prepared by facile electrochemical deposition and carbothermal reduction methods. Based on the MnO@CC cathode and a homemade gel polymer electrolyte, a flexible quasi-solid state ZIB was assembled and exhibited a high reversible capacity, a significant energy output of 345 Wh kg −1 , and excellent long-term cycling performance. The ultradispersed and well-crystallized octahedral MnO nanoparticle provides an improved ion transfer interface, and abundant Mn vacancy during the initial charging process provides sufficient inserted channels and available active sites for subsequent ion insertion and storage. In addition, for the as-activated MnO@CC electrode, the reversible coinsertion mechanism (H + and Zn 2+ ) is also monitored in the aqueous ZIBs. This work may provide insights into manufacturing advanced flexible aqueous ZIBs for wearable electronics via defect engineering.

Sodium Ion Pre-Intercalation of δ-MnO2 Nanosheets for High Energy Density Aqueous Zinc-Ion Batteries

“…This implies that there is sufficient oxidation and reduction in AZIBs for their prepared Na-MnO 2 cathode materials [ 12 ]. Furthermore, there was a clear voltage plateau at 1.2 V for the GCD curves of MnO 2 //Zn and Na-MnO 2 //Zn batteries, corresponding to the reduction peaks (1.18 V) from the CV curves ( Figure 3 b) [ 35 ]. Compared with the MnO 2 //Zn battery, the voltage gap of the Na-MnO 2 //Zn battery is narrower, further indicating that the pre-intercalation strategy of sodium can effectively improve redox reaction activity of δ-MnO 2 cathode materials [ 36 , 37 , 38 ].…”

Metal–Organic Framework‐Derived MnO/C Nanocomposite with Lamellar Porous Structure for High‐Performance Aqueous Zinc‐Ion Battery

“…Carbon materials have often been used in a number of applications due to their ability to effectively improve compound conductivity, enhance electron transport, and increase electrochemical activity. [5,[20][21][22][23] Carbon-coated MnO composites are an effective preparation method for MnO cathode material with superb performance because carbon can enhance MnO dispersity and reinforce the structural stability of MnO. Additionally, the carbon layer can inhibit the dissolution of Mn 2þ and reduce unwanted side reactions.…”

Chrysanthemum-like Polyaniline-Anchored PANI0.22·V2O5·0.88H2O-Hybridized Cathode for High-Stable Aqueous Zinc-Ion Batteries

“…Conventional lithium-ion batteries (LIBs) have revolutionized energy storage systems due to their excellent electrochemical performance and technical maturity. − However, in light of the concerns over the cost, safety, and availability of lithium reserves, they are an uncompetitive candidate for large-scale grid storage applications. As alternatives, battery chemistries based on more abundant elements (e.g., Na, K, Mg, Al, and Zn) have received extreme attention. , Among them, rechargeable Zn-ion batteries (ZIBs) can provide considerable merits in cost-effectiveness, high safety, and high anode capacity owing to zinc’s compatibility with non-flammable aqueous electrolytes, two-electron redox properties, and high abundance in the Earth’s crust. − However, one of the scientific challenges in implementing aqueous ZIBs is the shortage of suitable cathode materials to match the high capacity and robust structure during the repeat Zn 2+ (de)­intercalation.…”