Nanostructured alkali cation incorporated δ-MnO2 cathode materials for aqueous sodium-ion batteries

作者：Liu, Yang; Qiao, Yun; Zhang, Wuxing^*; Wang, Huan; Chen, Kongyao; Zhu, Huaping; Li, Zhen; Huang, Yunhui

来源：Journal of Materials Chemistry A, 2015, 3(15): 7780-7785.

DOI：10.1039/c5ta00396b

• LONG CYCLE LIFE
• ANODE MATERIALS
• HIGHLY EFFICIENT
• MANGANESE OXIDES
• WATER OXIDATION
• STORAGE
• PERFORMANCE
• NANOSHEETS
• OXYGEN
• SUPERCAPACITORS

Nanostructured delta-MnO2 incorporated with alkali cations (A-delta-MnO2, A = K+, Na+) has been synthesized and evaluated as a cathode material for aqueous sodium-ion batteries. It is observed that Na+ ions are easier than K+ ions to intercalate into the layered delta-MnO2 due to their smaller ion radius. The incorporation of K+ and Na+ into delta-MnO2 shows a great influence on the electrochemical performance of the layered delta-MnO2. The full cell with (K, Na)-co-incorporated delta-MnO2 (K : Na : Mn = 0.15 : 0.26 : 1) hierarchical nanospheres as the cathode and NaTi2(PO4)(3) as the anode exhibits a specific capacity of 74.6 mA h g(-1) at 150 mA g(-1), and the capacity remains at similar to 62% at a high current density of 600 mA g(-1). The electrochemical cycling does not induce observable structural degradation even after 200 cycles. K-incorporated and (K, Na)-co-incorporated delta-MnO2 electrodes have superior capacity and rate capability, which can be ascribed to their hierarchical structure and adequate crystallinity.

• 出版日期2015
• 单位河南师范大学; 华中科技大学