Visible-light photocatalytic performances of TiO2 nanoparticles modified by trace derivatives of PVA

Abstract

In order to study the visible-light photocatalytic activity and catalysis stability of nanocomposites, a TiO2-based visible-light photocatalyst is prepared by surface-modification of TiO2 nanoparticles using trace conjugated derivatives from polyvinyl alcohol (DPVA) via a facile method. The obtained DPVA/TiO2 nanocomposites are characterized by X-ray diffraction (XRD), Fourier transform infrared Spectra (FT-IR), scanning electron microscopy (SEM), UV-vis diffuse reflection spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS). With Rhodamine B (RhB) as a model pollutant, the visible-light photocatalytic activity and stability of DPVA/TiO2 nanocomposites are investigated by evaluating the RhB decomposition under visible light irradiation. The results reveal that the trace conjugated polymers on the TiO2 surface doesn’t change the crystalline and crystal size of TiO2 nanoparticles, but significantly enhances their visible-light absorbance and visible-light photocatalytic activity. The nanocomposite with the PVA and TiO2 mass ratio of 1∶200 exhibits the highest visible-light photocatalytic activity. The investigated nanocomposites exhibit well visible-light photoctatalytic stability. The photogenerated holes are thought as the main active species for the RhB photodegradation in the presence of the DPVA/TiO2 nanocomposites.

Keywords

• catalytic chemistry
• photocatalyst
• polyvinyl alcohol
• TiO2
• conjugated polymer
• visible-light photocatalysis