Boosting Magnesium Ion Storage Behavior via Heteroelement Doping in a Porous Tunnel Framework Cathode for Aqueous Mg‐Ion Batteries

• Published in: Chemistry, an Asian journal Vol. 18; no. 12; pp. e202300208 - n/a
• Main Authors: Li, Zhuo, Chen, Yuanyuan, Gong, Zhe, Liu, Yang, Wang, Guiling, Gao, Yinyi, Zhu, Kai, Cao, Dianxue
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 15.06.2023
• Subjects: aqueous magnesium-ion battery; Batteries; cathode materials; Cathodes; Cations; cations doping; Chemistry; Crystal lattices; Distortion; Doping; Electrochemical analysis; Electrode materials; Energy storage; Ion storage; Magnesium; Manganese; manganese oxide; Molecular sieves; Room temperature; manganese oxide; cathode materials; aqueous magnesium-ion battery; cations doping
• ISSN: 1861-4728; 1861-471X; 1861-471X
• DOI: 10.1002/asia.202300208

To relieve the overwhelming pressure on fossil energy, aqueous magnesium ion batteries attracted tremendous attention owing to their low cost and high safety. However, the cathode materials are apt to occur lattice distortion because of the electrostatic interaction between magnesium ions and crystal. The 2×2 manganese octahedral molecular sieve with potassium ions and water located in the tunnels (K‐OMS‐2), utilized as a cathode material for chargeable magnesium ions batteries, is exposed to irreversible Mg2+ intercalation/deintercalation due to lattice distortion, which heavily damages the electrochemical properties and declines the capacity. Herein, we carry out an ion doping strategy to overcome the above issues, leading to an enhanced Mg Mg2+ storage behavior. The Nb or V cation is successfully doped into K‐OMS‐2 by a facile reflux method under room temperature. The specific surface area is enlarged by the addition of cations, which promise a large electrode‐electrolyte contact area. The Nb and V doped K‐OMS‐2 present a capacity of 252.6 and 265.9 mAh/g at 20 mA/g, respectively. This work demonstrates an ion doping approach toward exploiting the stable and high‐capacity Mg‐ion battery cathode and provides potential cathode materials for a large‐scale aqueous Mg‐ion‐based energy storage system. Nb, V‐doped K‐OMS‐2 was prepared through a facile constant temperature reflux method. The enlarged specific capacity and stabilized tunnel structure realized an improved electrochemical performance.