Synthesis of Antimony-Embedded Silicon Oxycarbide Composite Materials from DVB-modified Silicone oil for High-performance Sodium-ion batteries
- 주제(키워드) 소듐이온전지 , 음극소재 , 안티모니
- 발행기관 고려대학교 대학원
- 지도교수 변동진
- 발행년도 2020
- 학위수여년월 2020. 2
- 학위구분 석사
- 학과 대학원 신소재공학과
- 원문페이지 67 p
- UCI I804:11009-000000127206
- DOI 10.23186/korea.000000127206.11009.0000951
- 본문언어 영어
- 제출원본 000046025516
초록/요약
Sodium ion batteries are not only cheaper to produce than lithium ion batteries, but also the uniform and rich reserves of sodium in the world, efforts are being made to utilize sodium ion batteries as next-generation large-capacity energy storage devices. Sb-based anode materials have emerged as one of the popular alloying materials for SIB due to their high theoretical capacity. However, Sb has the problem of capacity fading due to excessive volume expansion (about 390%). Among the buffer materials to overcome this disadvantages, SiOC has been studied but SiOC has a disadvantage of having a fixed and limited free-carbon domain. Here, Sb/SiOC-DVB composite was easily synthesized by heat treatment of DVB, a liquid carbon source, with silicone oil and Sb acetate. Sb nanoparticles were uniformly embedded in DVB-modified SiOC with increased free-carbon domains. This composite material showed stable cycling performance (344.5 mAh g-1 after 150 cycles at 0.2 C) and improved rate capability (197.5 mAh g-1 at 5 C) as the SIB anode. The improved electrochemical performance is due to the increased free-carbon domain in the SiOC matrix due to the addition of DVB, which makes the characteristics of the SiOC material more soft and elastic, suppressing the volume expansion, and increasing the electrical conductivity.
more목차
Abstract ........................................................................................................ Ⅰ
List of Figures .............................................................................................. Ⅱ
List of Tables ............................................................................................... Ⅲ
Chapter Ⅰ. Introduction ................................................................................ 1
1.1 Sodium-ion batteries ........................................................................... 1
1.2 Alloy-based Anode Material................................................................ 3
1.3 Silicon Oxycarbide Materials ............................................................... 5
Chapter Ⅱ. Experimental .............................................................................. 8
2.1 Materials Preparation ........................................................................... 8
2.1.1 Synthesis of the Sb/SiOC-DVB composite ................................. 8
2.1.2 Synthesis of the SiOC-DVB or pure SiOC material ................... 8
2.2 Characterization................................................................................... 10
2.3 Electrochemical Characterization....................................................... 11
Chapter Ⅲ. Results and Discussion ........................................................... 12
3.1 Characterization of Sb/SiOC-DVB Composite.................................. 12
3.2 Electrochemical Performance ............................................................ 29
3.3 Post-Mortem analysis ....................................................................... 42
Chapter Ⅳ. Conclusion ................................................................................ 47
Reference ..................................................................................................... 48
