Interfacial Designs of MXenes for Mild Aqueous Zinc‐Ion Storage

Abstract

Limited Li resources, high cost, and safety risks of using organic electrolytes have stimulated a strong motivation to develop non‐Li aqueous batteries. Aqueous Zn‐ion storage (ZIS) devices offer low‐cost and high‐safety solutions. However, their practical applications are at the moment restricted by their short cycle life arising mainly from irreversible electrochemical side reactions and processes at the interfaces. This review sums up the capability of using 2D MXenes to increase the reversibility at the interface, assist the charge transfer process, and thereby improve the performance of ZIS. First, they discuss the ZIS mechanism and irreversibility of typical electrode materials in mild aqueous electrolytes. Then, applications of MXenes in different ZIS components are highlighted, including as electrodes for Zn2+ intercalation, protective layers of Zn anode, hosts for Zn deposition, substrates, and separators. Finally, perspectives are put forward on further optimizing MXenes to improve the ZIS performance.

Hydrogel Electrolyte Enabled High‐Performance Flexible Aqueous Zinc Ion Energy Storage Systems toward Wearable Electronics

“…Besides, compared with the relatively stable AC cathode commonly used in ACCZIHCs, the cathode materials for AZIBs such as manganese oxides, [167] vanadium oxides, [168] Prussian blue analogs [169] and organic materials [170] all suffer from dissolution more or less. [171,172] According to the Jahn-Teller effect, manganese oxides and vanadium oxides may undergo irreversible lattice deformation during charging/discharging cycles, which makes them easier to be dissolved. [173,174] Typically, for manganese oxide cathodes, the dissolution of Mn 2+ stems from the disproportionation of Mn 3+ , and the Jahn-Teller effect may accelerate the disproportionation process.…”

Strategies Toward Stretchable Aqueous Zn‐based Batteries for Wearable Electronics from Components to Devices

“…Fourthly, the use of mild electrolytes, such as ZnSO 4 , Zn (CF 3 SO 3 ) 2 solutions, in AZBs in recent years can partly mitigate the formation of byproducts and zinc dendrites. [12,[20][21][22][23][24][25][26] Therefore, these advantages endow them with great potential in flexible and stretchable devices and directly lead to the rapid development of AZBs. [27] So far, extensive studies have been carried out to design flexible AZBs which mainly include Zn-air batteries, zinc-metal batteries, zinc-ion batteries, and so on.…”

“…Fourthly, the use of mild electrolytes, such as ZnSO 4 , Zn (CF 3 SO 3 ) 2 solutions, in AZBs in recent years can partly mitigate the formation of byproducts and zinc dendrites. [ 12,20–26 ] Therefore, these advantages endow them with great potential in flexible and stretchable devices and directly lead to the rapid development of AZBs. [ 27 ]…”

Construction of V2O5@MXene Cathodes toward a High Specific Capacity Aqueous Aluminum-Ion Battery

“…Two-dimensional (2D) MXene materials offer good electrical conductivity and pseudocapacitive properties due to the unique alternating structure of carbon and transition metal layers. The surface of MXene has abundant active sites and good hydrophilicity, which can be used as substrate to deposit metal oxides. ,,,− …”