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The rapid microwave-assisted hydrothermal synthesis of NASICON-structured Na3V2O2x(PO4)2F3-2x (0 $\less$ x $\leq$ 1) cathode materials for Na-ion batteriesстатья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 4 сентября 2019 г.
- Авторы: Burova Daria, Shakhova Iaroslava, Morozova Polina, Iarchuk Anna, Drozhzhin Oleg A., Rozova Marina G., Praneetha S., Murugan Vadivel, Tarascon Jean-Marie, Abakumov Artem M.
- Журнал: RSC advances
- Том: 9
- Номер: 34
- Год издания: 2019
- Издательство: Royal Society of Chemistry
- Местоположение издательства: United Kingdom
- Первая страница: 19429
- Последняя страница: 19440
- DOI: 10.1039/c9ra02257k
- Аннотация: NASICON-structured Na3V2O2x(PO4)2F3−2x (0 < x ≤ 1) solid solutions have been prepared using a microwave-assisted hydrothermal (MW-HT) technique. Well-crystallized phases were obtained for x = 1 and 0.4 by reacting V2O5, NH4H2PO4, and NaF precursors at temperatures as low as 180–200 °C for less than 15 min. Various available and inexpensive reducing agents were used to control the vanadium oxidation state and final product morphology. The vanadium oxidation state and O/F ratios were assessed using electron energy loss spectroscopy and infrared spectroscopy. According to electron diffraction and powder X-ray diffraction, the Na3V2O2x(PO4)2F3−2x solid solutions crystallized in a metastable disordered I4/mmm structure (a = 6.38643(4) Å, c = 10.62375(8) Å for Na3V2O2(PO4)2F and a = 6.39455(5) Å, c = 10.6988(2) Å for Na3V2O0.8(PO4)2F2.2). With respect to electrochemical Na+ (de)insertion as positive electrodes (cathodes) for Na-ion batteries, the as-synthesized materials displayed two sloping plateaus upon charge and discharge, centered near 3.5–3.6 V and 4.0–4.1 V vs. Na+/Na, respectively, with a reversible capacity of ∼110 mA h g−1. The application of a conducting carbon coating through the surface polymerization of dopamine with subsequent annealing at 500 °C improved both the rate capability (∼55 mA h g−1 at a discharge rate of 10C) and capacity retention (∼93% after 50 cycles at a discharge rate of C/2).
- Добавил в систему: Дрожжин Олег Андреевич