Volkov Filipp S, Eliseeva Svetlana N, Kamenskii Mikhail A, Volkov Alexey I, Tolstopjatova Elena G, Glumov Oleg V, Fu Lijun, Kondratiev Veniamin V
Institute of Chemistry, Saint Petersburg State University, 7/9 Universitetskaya Nab, 199034 Saint Petersburg, Russia.
State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China.
Nanomaterials (Basel). 2022 Nov 4;12(21):3896. doi: 10.3390/nano12213896.
In this work the nanocomposite of vanadium oxide with conducting polymer poly(3,4-ethylenedioxythiophene) (VO@PEDOT) was obtained by microwave-assisted hydrothermal synthesis. The detailed study of its structural and electrochemical properties as cathode of aqueous zinc-ion battery was performed by scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction analysis, X-ray photoelectron spectroscopy, thermogravimetric analysis, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. The initial VO@PEDOT composite has layered nanosheets structure with thickness of about 30-80 nm, which are assembled into wavy agglomerated thicker layers of up to 0.3-0.6 μm. The phase composition of the samples was determined by XRD analysis which confirmed lamellar structure of vanadium oxide VO∙12HO with interlayer distance of about 13.6 Å. The VO@PEDOT composite demonstrates excellent electrochemical performance, reaching specific capacities of up to 390 mA∙h∙g at 0.3 A∙g. Moreover, the electrodes retain specific capacity of 100 mA∙h∙g at a high current density of 20 A∙g. The phase transformations of VO@PEDOT electrodes during the cycling were studied at different degrees of charge/discharge by using ex situ XRD measurements. The results of ex situ XRD allow us to conclude that the reversible zinc ion intercalation occurs in stable zinc pyrovanadate structures formed during discharge.
在这项工作中，通过微波辅助水热合成法制备了氧化钒与导电聚合物聚（3,4 - 乙撑二氧噻吩）的纳米复合材料（VO@PEDOT）。通过扫描电子显微镜、能量色散X射线分析、X射线衍射分析、X射线光电子能谱、热重分析、循环伏安法、恒电流充放电和电化学阻抗谱等方法，对其作为水系锌离子电池正极的结构和电化学性能进行了详细研究。初始的VO@PEDOT复合材料具有层状纳米片结构，厚度约为30 - 80 nm，这些纳米片组装成厚度达0.3 - 0.6μm的波浪状团聚较厚层。通过XRD分析确定了样品的相组成，证实了氧化钒VO∙12HO的层状结构，其层间距约为13.6 Å。VO@PEDOT复合材料表现出优异的电化学性能，在0.3 A∙g时比容量高达390 mA∙h∙g。此外，电极在20 A∙g的高电流密度下仍保持100 mA∙h∙g的比容量。通过非原位XRD测量，研究了VO@PEDOT电极在不同充放电程度下循环过程中的相变。非原位XRD的结果使我们能够得出结论，可逆的锌离子嵌入发生在放电过程中形成的稳定焦钒酸锌结构中。
