Regulation of morphology and visible light-driven photocatalysis of WO3nanostructures by changing pH

The controlled preparation of hexagonal tungsten trioxide (h-WO3) nanostructures was achieved by adjusting the pH of the precursor solution. The effect of the pH on the morphology, elemental composition, and photocatalytic performance of the samples was characterized via X-ray diffraction (XRD), scanning electron microscopy, energy dispersive X-ray spectroscopy, and Raman spectroscopy. Ultraviolet-visible (UV-Vis) spectra were used to evaluate the absorbance and the photocatalytic performance of methylene blue. Photoluminescence (PL), electrochemical impedance spectroscopy, photocurrent response and Brunauer-Emmett-Teller (BET) were used to study the optical properties, electrical performance, and specific surface area of the WO(3-)nanostructures, respectively. The results indicate that the WO(3)nanorods prepared at pH = 1.0 exhibit the highest photocatalytic performance (87.4% in 1 h), whereas the WO(3)nanoblocks prepared at pH = 3.0 show the lowest. The photocatalytic performance of the one dimensional (1D)-nanorods can be attributed to their high specific surface area and charge transfer ability. The h-WO(3)nanostructures were synthesized via a simple method and without a capping agent. They show an excellent photocatalytic performance, which is promising for their application in environment purification.

Automated summary

Controlled preparation of hexagonal tungsten trioxide nanostructures was achieved by adjusting the pH of the precursor solution. The WO(3) nanostructures prepared at different pH values exhibited varying photocatalytic performances, with nanorods prepared at pH = 1.0 showing the highest performance.