Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7733065 | Journal of Power Sources | 2015 | 7 Pages |
Abstract
Within this study we report on the impact of the pyrolysis temperature on the structural and electrochemical properties of the poly(phenylvinylsilylcarbodiimide) derived silicon carbonitride (SiCN) ceramic. Materials pyrolysed at 800 °C and 1300 °C, SiCN 800 and SiCN 1300, are found amorphous. Raman spectroscopy measurements indicate the increase in ordering of the free carbon phase with increasing pyrolysis temperature which leads to lower capacity recovered by SiCN 1300. Significant hysteresis is found for materials pyrolysed at 800 °C during electrochemical lithium insertion/extraction. This feature is attributed to much higher hydrogen content in SiCN 800 sample. An aging of SiCN 800 reflected by a change of elemental composition upon contact to air and a strong film formation are attenuated at a higher pyrolysis temperature. Single particle microelectrode investigation on SiCN 800 and SiCN 1300 clarify different electrochemical behavior of the materials. Much lower charge transfer resistance of SiCN 1300 in comparison to SiCN 800 explains better high currents electrochemical performance. Lithium ions diffusion coefficient Dmin ranges from 3.2 10â9 cm2sâ1 to 6.4 10-11 cm2sâ1 and is independent on the potential.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Lukas Mirko Reinold, Yuto Yamada, Magdalena Graczyk-Zajac, Hirokazu Munakata, Kiyoshi Kanamura, Ralf Riedel,