Abstract:
The TiO2·[Y2O3]x (x = 0.1–0.4) nanocomposites (NCs) with an average particle size of 74 nm
were prepared by the method of chemical co-precipitation followed by hydrolysis (CPH). Their
visible light photocatalytic activity was investigated for the degradation of congo red (CR) dye.
All NCs showed improved degradation as compared to the polycrystalline samples of similar
compositions prepared by the solid-state reaction (SSR) route (average particle size of a few
micrometers), as well as to the pure TiO2. The better photocatalytic activity of the NCs was
attributed to their smaller particle size. Another comparison of the results with those obtained
with Zn2+/Fe3+ ions co-doped TiO2 NCs, under similar experimental conditions, revealed that
in the Y3+-doped NCs, particle size might not be the only factor responsible for the improved
photocatalytic properties. It was concluded that the Y3+ ion-mediated suppression of the
unwanted e−/h+ recombination could be the possible factor leading to additional enhancement.