کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1287818 1497996 2013 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Carbon-rich SiCN ceramics as high capacity/high stability anode material for lithium-ion batteries
موضوعات مرتبط
مهندسی و علوم پایه شیمی الکتروشیمی
پیش نمایش صفحه اول مقاله
Carbon-rich SiCN ceramics as high capacity/high stability anode material for lithium-ion batteries
چکیده انگلیسی

Two classes of preceramic polymers, namely polysilazane and polysilylcarbodiimide, with branched and linear molecular structure were pyrolyzed at 1100 °C under argon atmosphere. The resulting nanostructured polymer-derived SiCN ceramics were characterized by means of elemental analysis, X-ray diffraction, scanning electron microscopy and Raman spectroscopy. All investigated ceramics are amorphous and contain a disordered free carbon phase of 2–2.5 nm in size. Electrochemical characterization reveals that the polysilazane-derived electrodes demonstrate higher capacity and stability during subsequent lithium insertion/extraction with different currents than those of the polysilylcarbodiimide-based electrodes. The highest lithium extraction capacity of 724 mA h g−1 is recovered for the sample derived from branched polysilazane whereas the best polysilylcarbodiimide-derived sample recovers 612 mA h g−1. Moreover, the polysilazane-derived samples deliver a higher fraction of capacity recovered below 1.5 V. The electrochemical performance is found to be dependent on the molecular structure (silazane vs. silylcarbodiimide) of the preceramic polymer, while there is no effect associated with the amount of branching (silsesquiazane vs. silazane and silsesquicarbodiimide vs. silylcarbodiimide). The influence of “micropore activity” and oxygen content on the electrochemical performance of polymer-derived silicon carbonitrides is addressed.


► SiCN ceramics were investigated in terms of Li-ion storage capacity.
► Influence of microstructure on electrochemical properties of SiCN was studied.
► Oxygen to nitrogen ratio was found to be irrelevant for capacity of SiCN.
► SiCN is potential candidate to replace graphite anodes in lithium-ion batteries.
► No linear relationship between free carbon content and capacity was found for SiCN.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Power Sources - Volume 236, 15 August 2013, Pages 224–229
نویسندگان
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