콘텐츠 본문
논문 해외 국제전문학술지(SCI급) Tuning sodium nucleation and stripping by the mixed surface of carbon nanotube-sodium composite electrodes for improved reversibility
- 학술지 구분 국제전문학술지(SCI급)
- 게재년월 2019-10
- 저자명 유명현,김윤정,이진홍,육승민,노형준,추현원,곽호범,김석우,김희탁
- 학술지명 JOURNAL OF POWER SOURCES
- 발행처명 ELSEVIER
- 발행국가 해외
- 논문언어 외국어
- 전체저자수 9
- 논문 다운로드 링크(외부) https://doi.org/10.1016/j.jpowsour.2019.227005
- 연구분야 공학 > 화학공학
논문 초록 (Abstract)
Metallic sodium is regarded as a promising anode material for sodium rechargeable batteries. However, sodium dendrite growth and exhaustive electrolyte decomposition cause the poor reversibility of the sodium metal electrode. Here, we present that, by forming a mixed surface of carbon and sodium metal, the sodium electrodeposition mode and stripping mechanism can be tuned. In order to systematically investigate sodium plating/stripping behavior on a mixed surface of carbon and sodium, we fabricate a carbon nanotube-sodium composite electrode with a simple rolling and folding method. As the carbon nanotube content is increased, the overpotentials for sodium nucleation and pit-formation are remarkably reduced. Postmortem and chronoamperometry analysis elucidate that sodium and sodiated carbon nanotube have a different sodium nucleation mode, and sodium nucleation is preferred on the sodiated carbon nanotube surface with lower nucleation energy, inducing a more uniform sodium deposition. Furthermore, the embedded carbon nanotube appears to help sodium stripping by providing a channel for a more facile sodium ion transport. As a result, the carbon nanotube-sodium composite electrode exhibites a 5 times higher cycling stability. The tuning of the nucleation and stripping behaviors by forming a mixed surface can be a viable approach for enhancing the reversibility of metal electrode.
