Konar Rajashree, Perelshtein Ilana, Teblum Eti, Telkhozhayeva Madina, Tkachev Maria, Richter Jonathan J, Cattaruzza Elti, Pietropolli Charmet Andrea, Stoppa Paolo, Noked Malachi, Nessim Gilbert Daniel
Chemistry, Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 52900, Israel.
Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 52900, Israel.
ACS Omega. 2020 Jul 24;5(31):19409-19421. doi: 10.1021/acsomega.0c01155. eCollection 2020 Aug 11.
We report a facile two-furnace APCVD synthesis of 2H-WSe. A systematic study of the process parameters is performed to show the formation of the phase-pure material. Extensive characterization of the bulk and exfoliated material confirm that 2H-WSe is layered (i.e., 2D). X-ray diffraction (XRD) confirms the phase, while high-resolution scanning electron microscopy (HRSEM), high-resolution transmission electron microscopy (HRTEM), and atomic force microscopy (AFM) clarify the morphology of the material. Focused ion beam scanning electron microscopy (FIB-SEM) estimates the depth of the 2H-WSe formed on W foil to be around 5-8 μm, and Raman/UV-vis measurements prove the quality of the exfoliated 2H-WSe. Studies on the redox processes of lithium-ion batteries (LiBs) show an increase in capacity up to 500 cycles. On prolonged cycling, the discharge capacity up to the 50th cycle at 250 mA/g of the material shows a stable value of 550 mAh/g. These observations indicate that exfoliated 2H-WSe has promising applications as an LiB electrode material.
我们报道了一种通过双炉常压化学气相沉积（APCVD）合成2H-WSe₂的简便方法。对工艺参数进行了系统研究，以展示纯相材料的形成。对块状和剥离后的材料进行了广泛表征，证实2H-WSe₂是层状的（即二维的）。X射线衍射（XRD）确定了相，而高分辨率扫描电子显微镜（HRSEM）、高分辨率透射电子显微镜（HRTEM）和原子力显微镜（AFM）则阐明了材料的形态。聚焦离子束扫描电子显微镜（FIB-SEM）估计在钨箔上形成的2H-WSe₂的深度约为5-8μm，拉曼光谱/紫外可见光谱测量证明了剥离后的2H-WSe₂的质量。对锂离子电池（LiBs）氧化还原过程的研究表明，在500次循环内容量有所增加。在长时间循环中，该材料在250 mA/g下第50次循环时的放电容量显示出稳定值550 mAh/g。这些观察结果表明，剥离后的2H-WSe₂作为锂离子电池电极材料具有广阔的应用前景。
