摘要
Manganese dioxide(MnO_(2)),as a cathode material for multivalent ion(such as Mg^(2+)and Al^(3+))storage,is investigated due to its high initial capacity.However,during multivalent ion insertion/extraction,the crystal structure of MnO_(2)partially collapses,leading to fast capacity decay in few charge/discharge cycles.Here,through pre-intercalating potassium-ion(K+)intoδ-MnO_(2),we synthesize a potassium ion pre-intercalated MnO_(2),K_(0.21)MnO_(2)·0.31H_(2)O(KMO),as a reliable cathode material for multivalent ion batteries.The as-prepared KMO exhibits a high reversible capacity of 185 mAh/g at 1 A/g,with considerable rate performance and improved cycling stability in 1 mol/L MgSO_(4)electrolyte.In addition,we observe that aluminum-ion(Al^(3+))can also insert into a KMO cathode.This work provides a valid method for modifcation of manganesebased oxides for aqueous multivalent ion batteries.
基金
supported by the National Natural Science Foundation of China(Grant No.52102264)
the Leading Edge Technology of Jiangsu Province(BK20220009)
the Open Project Program of Wuhan National Laboratory for Optoelectronics(No.2020WNLOKF011).
