材料科学
无定形固体
电极
电池(电)
离子
锂(药物)
化学工程
纳米技术
结晶学
有机化学
物理化学
热力学
物理
工程类
内分泌学
功率(物理)
化学
医学
作者
Dongliang Chao,Ryan H. DeBlock,Chun‐Han Lai,Qiulong Wei,Duncan W. Bruce,Hong Jin Fan
标识
DOI:10.1002/adma.202103736
摘要
Among the various VO2 polymorphs, the layered compound, VO2 (B), has been the most widely investigated lithium-ion battery electrode material. For sodium-ion electrodes, however, an amorphous solid may be more advantageous as a result of the open framework to facilitate ion insertion and the ability to tolerate volumetric changes. Herein, it is shown that the Na+ insertion properties of amorphous VO2 (a-VO2 ) are superior to those of crystalline VO2 (B). Amorphous VO2 exhibits a linear voltage characteristic over a 3 V range (4.0 to 1.0 V vs Na/Na+ ) leading to a reversible capacity as high as 400 mAh g-1 and rapid redox kinetics, which is attributed to its pseudocapacitive nature. The linear voltage characteristic over 3 V affords the opportunity of fabricating a symmetric Na-ion battery in which the a-VO2 material serves as both the positive electrode and the negative electrode. Such a symmetric battery offers safer operation in terms of overcharging, overdischarging, polarity reversal, high charge/discharge current abuse, and long-term usage. The results suggest that amorphous transition metal oxides may offer advantageous attributes for rapid, safe, and energy-dense storage.
科研通智能强力驱动
Strongly Powered by AbleSci AI