Published November 25, 2021
| Version v1
Publication
Effect of synthesis pH on the physicochemical properties of a synthesized Bi2WO6 and the type of substrate chosen, in assessing its photo-catalytic activities
Contributors
Description
Crystalline orthorhombic Bi2WO6 powders were synthesized by a hydrothermal method
from aqueous solutions of Bi(NO3)3 5H2O and Na2WO4 2H2O over a range of three selected pH
values (2.0, 5.0 and 7.0), using NaOH as precipitating agent. The as-prepared catalysts were char-
acterized by XRD, BET, FE-SEM, TEM, XPS and UV-vis spectroscopy. The effect of pH-synthesis
on crystallinity, morphologies, surface area and optical absorption properties, were investigated.
Although the pH has a marked influence on morphology, the nature of the precipitating agent
(NaOH or TEA) also influences the morphology and surface structure composition, as it is
observed in the present work. Three different probe molecules were used to evaluate the photo-
catalytic properties under two illumination conditions (UV and Visible): Methyl Orange and Rho-
damine B were chosen as dye substrates and Phenol as a transparent substrate. The photo-catalytic
activities are strongly dependent not only on the pH used in the synthesis but also on the nature of
the chosen substrate in assessing the photo-catalytic activities. Results were compared with those
obtained when using TiO2(P25, Evonik) in the same experimental conditions. The photo-
catalytic activity of one of the synthesised samples has been evaluated by exposing a mixture of
Rhodamine B and Phenol in water, to different illumination conditions. Our results provide new
evidences about the issue of whether dyes are suitable substrates to assess the activity of a
photo-catalyst.
Additional details
Identifiers
- URL
- https://idus.us.es/handle//11441/127686
- URN
- urn:oai:idus.us.es:11441/127686