Scalable Synthesis of Few-Layered 2D Tungsten Diselenide (2H-WSe2) Nanosheets Directly Grown on Tungsten (W) Foil Using Ambient-Pressure Chemical Vapor Deposition for Reversible Li-Ion Storage

Rajashree Konar; Rosy; Ilana Perelshtein; Eti Teblum; Madina Telkhozhayeva; Maria Tkachev; Jonathan J Richter; Elti Cattaruzza; Andrea Pietropolli Charmet; Paolo Stoppa; Malachi Noked; Gilbert Daniel Nessim

doi:10.1021/acsomega.0c01155

Scalable Synthesis of Few-Layered 2D Tungsten Diselenide (2H-WSe₂) Nanosheets Directly Grown on Tungsten (W) Foil Using Ambient-Pressure Chemical Vapor Deposition for Reversible Li-Ion Storage

ACS Omega. 2020 Jul 24;5(31):19409-19421. doi: 10.1021/acsomega.0c01155. eCollection 2020 Aug 11.

Affiliations

¹ Chemistry, Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 52900, Israel.
² Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 52900, Israel.
³ Department of Molecular Sciences and Nanosystems, Ca'Foscari University of Venice, Via Torino, 155, Venezia-Mestre 30172, Italy.

Abstract

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.