Synthesis of Atomically Thin WO3 Sheets from Hydrated Tungsten Trioxide

Research areas:
  • Uncategorized
Year: 2010
Type of Publication: Article
  • Kourosh Kalantar-zadeh, Moon-Ho Ham Aravind Vijayaraghavan
Journal: Chemistry of Materials Volume: 22
Number: 19 Pages: 5660-5666
Month: OCT 12 2010
PT: J; TC: 22; UT: WOS:000282471000032
Atomically thin WO3 is fabricated using a three-step process, involving wet-chemical synthesis of hydrated-WO3, mechanical exfoliation of fundamental layers and dehydration by annealing at 300 degrees C. Atomic force microscopy reveals that the minimum resolvable thickness of the hydrated flakes to be similar to 1.4 nm, which corresponds to the unit-cell height. The subsequent annealing temperature determines the degree of dehydration and thereby the crystallographic structure of the resultant WO3. The hydrated and dehydrated flakes are characterized by Raman spectroscopy to reveal spectroscopic fingerprints of flake thickness. Thin flakes arc also shown to have higher propensity for lithium intercalation, which is also evidenced in Raman planar peak intensity.