AI 中文总结
研究从理论和实验角度，采用熔盐法用ZnCl2蚀刻Ti2InB2制备多层Ti2B2Clx MBene，通过多种表征手段和理论计算证实相关过程，评估其锂离子电池性能，为二维材料开发提供通用方法。
AI 中文摘要
二维材料独特性质及应用潜力促使对不同纳米层状化合物的探索。本文采用熔盐法，用ZnCl2选择性蚀刻Ti2InB2制备多层Ti2B2Clx MBene。扫描透射电子显微镜等表明蚀刻后In原子被氯表面终端取代，覆盖率为1.1 < x < 1.4。原位X射线衍射显示从Ti2InB2到多层MBene的直接双相转变。基于密度泛函理论的计算框架证实了实验观察。A元素取代3D Ti2ZnB2相预计为吸热反应。初步锂离子电池性能评估显示其放电容量稳定。理论框架与材料合成及表征相结合为二维材料开发提供了通用方法。
英文摘要
The unique properties and application possibilities of two-dimensional (2D) materials motivates the exploration of different nanolaminated compounds. Here, by using a molten salt approach, we selectively etch Ti2InB2 with ZnCl2 to produce a multilayer (ml) Ti2B2Clx MBene. Scanning transmission electron microscopy, in combination with energy dispersive X-ray, and electron energy loss spectroscopies show that In atoms are completely removed from the precursor upon etching, being replaced by chlorine surface terminations with a coverage 1.1 < x < 1.4. Further, in situ X-ray diffraction indicates a direct biphasic transformation from Ti2InB2 to ml-MBene, with no signs of intermediate phase formation. A computational framework based on density functional theory further corroborates these experimental observations by showing a negative reaction free energy for the formation of ml-MBene, favourable over all competing processes. In addition, A-element substitution into to the 3D Ti2ZnB2 phase is predicted to be endergonic, consistent with the absence of experimental evidence for its formation. Initial Li-ion battery performance evaluation showed a stable discharge capacity similar or better than MAX phases and other borides. Altogether, the theoretical framework combined with materials synthesis and characterization provides a general approach for 2D materials development, for further expansion of the family of 2D materials.
Comments4 figures, 27 pages
