Development of Microwave-Assisted Graphene Exfoliation for High Performance Si/Graphene Anode in Secondary Lithium Ion Battery
Yi-Chen Hsieh1*, Hsiao-Chien Wang1, Wen-Chun Yen2, Stuart R. Thomas1, Yu-Lun Chueh1
1Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan
2Giga Solar Materials Corporation, Hsinchu, Taiwan
* presenting author:Yi-Chen Hsieh,
Silicon has become one of the most promising anode material candidates for use in lithium ion batteries due to its high specific capacity (3579 mAh/g), almost ten times larger than current commercial graphite anodes. However, poor cycle lifetime, caused by ~400 % volume change during alloying, is currently the biggest challenge toward their commercial application. The use of graphene offers one potential method to overcome this problem. However, to be effective, a facile route toward reduced graphene synthesis will be required.

In this work, we demonstrate an efficient, low cost method to exfoliate and reduce graphene oxide simultaneously under a minute, utilizing silicon carbide (SiC) as an efficient microwave susceptor heat source. Our graphene oxide precursor was placed in contact with a SiC disk under vacuum, and under application of microwave radiation our graphene oxide undergoes a rapid heating and reduction to graphene. The influence of applied microwave power and duration was investigated and we are able to obtain reduced graphene at a power of only 400W in less than one minute. Fourier transform infrared spectroscopy (FTIR) and X-Ray photoelectron spectroscopy (XPS) were used to observe the loss of C=O peaks and OH peaks confirming the reduction of our graphene oxide post microwave treatment. We believe this work presents a highly promising technique toward the low-cost production of reduced graphene oxide suitable for future Si based Li-ion battery applications.

Keywords: microwave, graphene oxide, reduced graphene oxide, lithium ion battery