A Water Based Synthesis of Ultrathin Hydrated Vanadium Pentoxide Nanosheets for Lithium Battery Application: Free Standing Electrodes or Conventionally Casted Electrodes?

作者：Etman, Ahmed S.; Inge, A. Ken; Xu Jiaru; Younesi, Reza; Edstrom, Kristina^*; Sun, Junliang^*

来源：Electrochimica Acta, 2017, 252: 254-260.

DOI：10.1016/j.electacta.2017.08.137

• V2O5 center dot nH(2)O nanosheets
• lithium battery
• free standing
• water based synthesis

Ultrathin hydrated vanadium pentoxide (V2O5 center dot nH(2)O) nanosheets are fabricated via a water based exfoliation technique. The exfoliation process involves reflux of the precursor, 1:4 mixture of VO2 and V2O5, in water at 80 degrees C for 24 h. Operando and ex situ X-ray diffraction (XRD) studies are conducted to follow the structural changes during the exfoliation process. The chemical and thermal analyses suggest that the molecular formula of the nanosheet is (H0.2V1.8V0.2O5)-V-V-O-IV center dot 0.5H(2)O. The V2O5 center dot nH(2)O nanosheets are mixed with 10% of multi-walled carbon nanotube (MW-CNT) to form a composite material assigned as (VOx-CNT). Free standing electrodes (FSE) and conventionally casted electrodes (CCE) of VOx-CNT are fabricated and then tested as a positive electrode material for lithium batteries. The FSE shows reversible capacities of 300 and 97 mAhg(-1) at current densities of 10 and 200 mAhg(-1), respectively. This is better than earlier reports for free-standing electrodes. The CCE delivers discharge capacities of 175 and 93 mAhg(-1) at current densities of 10 and 200 mAhg(-1), respectively.

• 出版日期2017-10-20
• 单位北京大学