A Facile Synthesis of Graphene-WO₃Nanowire Clusters with High Photocatalytic Activity for O₂Evolution

Abstract

In the present work, graphene-WO 3 nanowire clusters were synthesized via a facile hydrothermal method. The obtained graphene-WO 3 nanowire clusters were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Xray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and ultravioletvisible diffuse reflectance spectroscopy (DRS) techniques. The photocatalytic oxygen (O 2 ) evolution properties of the as-synthesized samples were investigated by measuring the amount of evolved O 2 from water splitting. The graphene-WO 3 nanowire clusters exhibited enhanced performance compared to pure WO 3 nanowire clusters for O 2 evolution. The amount of evolved O 2 from water splitting after 8 h for the graphene-WO 3 nanowire clusters is ca. 0.345 mmol/L, which is more than 1.9 times as much as that of the pure WO 3 nanowire clusters (ca. 0.175 mmol/L). The high photocatalytic activity of the graphene-WO 3 nanowire clusters was attributed to a high charge transfer rate in the presence of graphene.

Photocatalytic Oxygen Evolution from Water Splitting

“…In Figure 20p–r, the WO 3 /graphene nanowires with different mass ratios of graphene that were prepared by a facile hydrothermal route displayed higher O 2 evolution performance than the WO 3 nanowires, because graphene promoted the separation efficiency of charge carriers by accepting the photogenerated electrons from WO 3 . [ 147 ] Due to the existence of the low resistance conduction path, the WO 3 /graphene with the particle diameter of ≈12 nm exhibited higher O 2 evolution production than bare WO 3 and physically mixed WO 3 and graphene (Figure 20s–u). [ 148 ] Similarly, the photocatalytic activity of α ‐Fe 2 O 3 was also elevated by coupling with reduced graphene oxide (rGO) as the electron transfer platform (Figure 20v–x).…”

Oxide vacancies enhanced visible active photocatalytic W19O55NMRs via strong adsorption

“…The recorded UV-vis absorption spectrum reveals that the annealed sample (WO 3 NMRs) has a strong absorption band to light in the wavelength range from 200 to 410 nm, which is in accordance with the already reported UV-vis absorption spectra of WO 3 materials in literature. 17,33 For the as-synthesized W 19 O 55 NMRs, the UV-vis absorption spectrum presents a more complicated prole than that of its corresponding annealed counterpart. Besides the strong absorption band from 200 to 404 nm, which is similar with that of WO 3 , another strong wide absorption band (centred at around 600 nm) can be observed in the visible region from 470 to 740 nm.…”

Modified WO3 nanosheets by N-GO nanocomposites to form NO2 sensor

“…Surface accessibility and active gas diffusion between matching layers of graphene enhances by the introduction of WO 3 nanosheets, which also avoids the GO sheets from restacking. To estimate the crystallite size of the nanocomposites, the Williamson-Hall plot was used [56]. The data are collected in Table 1.…”