Local structure study of vanadium pentoxide 1D-nanostructures

Abstract

Vanadium pentoxide (V 2 O 5 ÁnH 2 O) 1D-nanostructures as nanowires and nanorods have been obtained by decomposition of vanadium peroxide in hydrothermal conditions. Electron microscopy, Raman spectroscopy, and X-ray absorption spectroscopy (XAS) were employed to characterize the morphology and the local structure of as-obtained samples. Scanning transmission electron microscopy (STEM) revealed that the diameter of the nanowires and nanorods were found to be 10-20 and 30-40 nm, respectively. The results demonstrated that a combination of Raman and XAS techniques allowed the accurate characterization of the local structure of V 2 O 5 1D-nanostructures which are related to different morphologies. Analyses of X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra reveals that the local structure of V in the as-obtained samples is similar to the bulk V 2 O 5 (in orthorhombic phase), except for a higher degree of local symmetry within the structure of the VO 5 square pyramid. Additionally, the nanostructures prepared by this technique present a single crystalline nature and could emit visible light at room temperature which is related to the local order of V atoms of the studied samples.

Crystallizing Vanadium Pentoxide Nanostructures in the Solid‐State Using Modified Block Copolymer and Chitosan Complexes

“…The observed PL spectra of the PS-co-4-PVP⋅(VCl 3 ) y and chitosan⋅(VCl 3 ) y pyrolytic product are showed in Figure 8. The intense and sharp emission peak observed at 458 nm is assigned to the near band edge that is assigned to transitions of electrons between valence (O-2p) and conduction band (V-3d) and usually observed for V 2 O 5 [79,87,88]. On the other hand the emission peak observed at 588 nm is caused by the surface defects and also observed for V 2 O 5 using several preparation methods [49,69].…”

Studies on dispersion and reactivity of vanadium oxides deposited on lamellar ferrierite zeolites for condensation of glycerol into bulky products

“…4. In these materials, the pre-edge peak at around 5470 eV, due to 1s to 3d dipole-forbidden transitions, provides an indication of the degree of distortion of oxygen atoms in the first coordination sphere, which are affected by the degree of hybridization between the 2p and 3d orbitals [49,50]. When the degree of hybridization increases, the distance between the neighboring oxygen atoms becomes smaller and the pre-edge intensity increases.…”

Spectroscopic study of native defects in the semiconductor to metal phase transition in V2O5 nanostructure

“…The highest frequency Raman mode at 993 cm -1 arises due to the vibration of terminal oxygen atoms along Z direction and is a signature peak for V 2 O 5 . 18,19 The peak at 850 cm -1 is predicted to originate because of antiphase stretching mode of V-O II bonds. 16 19,20 The Raman mode at 850 cm -1 is reported not to be observed experimentally due to the pseudo-centrosymmetric nature of V−OII−V bond.…”