We report a facile two-furnace APCVD synthesis of 2H-WSe2. 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-WSe2 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-WSe2 formed on W foil to be around 5-8 μm, and Raman/UV-vis measurements prove the quality of the exfoliated 2H-WSe2. 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-WSe2 has promising applications as an LiB electrode material.
Bibliographical noteFunding Information:
G.D.N. is thankful to the Israel Science Foundation and Israel Prime Ministry Office for alternatives initiative for partial funding of this study under the Israel Research center for Electrochemical Propulsion (INREP) (Grant: ISF 2797/11) and European Union’s Horizon 2020 research and innovation program under grant agreement no. 814413, project ADMAIORA. Madina Telkhozhayeva is thankful to Erasmus + ICM (ERASMUS + KA107 ICM).
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