期刊
JOURNAL OF MATERIALS CHEMISTRY A
卷 8, 期 2, 页码 750-759出版社
ROYAL SOC CHEMISTRY
DOI: 10.1039/c9ta09750c
关键词
-
资金
- US National Science Foundation [1603847, 1603491, 1604104]
- Robert A. Welch Foundation [F-1436]
- DOE Office of Science [DE-AC02-06CH11357]
- Directorate For Engineering
- Div Of Chem, Bioeng, Env, & Transp Sys [1603847, 1603491] Funding Source: National Science Foundation
- Directorate For Engineering
- Div Of Chem, Bioeng, Env, & Transp Sys [1604104] Funding Source: National Science Foundation
To understand the effect of selenium doping on the good cycling performance and rate capability of a Ge0.9Se0.1 electrode, the dynamic morphological and phase changes of the Ge0.9Se0.1 electrode were investigated by synchrotron-based operando transmission X-ray microscopy (TXM) imaging, X-ray diffraction (XRD), and X-ray absorption spectroscopy (XAS). The TXM results show that the Ge0.9Se0.1 particle retains its original shape after a large volume change induced by (de)lithiation and undergoes a more sudden morphological and optical density change than pure Ge. The difference between Ge0.9Se0.1 and Ge is attributed to a super-ionically conductive Li-Se-Ge network formed inside Ge0.9Se0.1 particles, which contributes to fast Li-ion pathways into the particle and nano-structuring of Ge as well as buffering the volume change of Ge. The XRD and XAS results confirm the formation of a Li-Se-Ge network and reveal that the Li-Se-Ge phase forms during the early stages of lithiation and is an inactive phase. The Li-Se-Ge network also can suppress the formation of the crystalline Li15Ge4 phase. These in situ and operando results reveal the effect of the in situ formed, super-ionically conductive, and inactive network on the cycling performance of Li-ion batteries and shed light on the design of high capacity electrode materials.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据