| 학회 |
한국화학공학회 |
| 학술대회 |
2014년 가을 (10/22 ~ 10/24, 대전 DCC) |
| 권호 |
20권 2호, p.2415 |
| 발표분야 |
영어심포지엄(주제미정)(분리기술부문위원회 주제별 심포지엄) |
| 제목 |
Atomistic observation of the lithiation and delithiation behaviors of silicon nanowires using reactive molecular dynamics simulations |
| 초록 |
In this talk, we will discuss the mechanisms for the lithiation and delithiation of Si NWs determined using a large-scale molecular dynamics (MD) simulation with a reactive force field (ReaxFF). The ReaxFF is developed using results from first-principles calculations for various crystals and molecules. During the lithiation process, Li atoms penetrate into the lattices of the crystalline Si (c-Si) NWs preferentially along the ＜110＞ or ＜112＞ direction, and then the c-Si changes into amorphous LixSi (a-LixSi) phases due to the simultaneous breaking of Si-Si bonds as a result of the tensile stresses between Si atoms. Before the complete amorphization of the Si NWs, we observe the formation of silicene-like structures in the NWs that are eventually broken into low-coordinated components, such as dumbbells and isolated atoms. Additionally, during delithiation of LixSi NWs, we observe the formation of a small amount of c-Si nuclei in the a-LixSi matrix below a composition of Li1.4Si ~ Li1.5Si, and we demonstrate that the two-phase structure can be thermodynamically more favorable than the single-phase a-LixSi. |
| 저자 |
Sang Soo Han1, Hyun Jung2, Minho Lee1, Byung Chul Yeo1, Kwang-Ryeol Lee1
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| 소속 |
1KIST, 2KIST / Hanyang Univ. |
| 키워드 |
Silicon nanowire; lithiation; delithiation; reactive force field; molecular dynamics simulation
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| E-Mail |
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| VOD |
VOD 보기 |
| 원문파일 |
초록 보기 |
