Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10625866 | Ceramics International | 2013 | 8 Pages |
Abstract
A series of novel hafnium (Hf) doped ZnO nanophotocatalyst were synthesized using a simple sol-gel method with a doping content of up to 6Â mol%. The structure, morphology and optical characteristics of the photocatalysts were characterized by XRD, SEM, TEM, FTIR, XPS, DRS and PL spectroscopy. The successful synthesis and chemical composition of pure and doped ZnO photocatalysts were confirmed by XRD and XPS. DRS confirmed that the spectral responses of the photocatalysts were shifted towards the visible light region and showed a reduction in band gap energy from 3.26 to 3.17Â eV. Fluorescence emission spectra indicated that doped ZnO samples possess better charge separation capability than pure ZnO. The photocatalytic activity of Hf-doped ZnO was evaluated by the methylene blue (MB) degradation in aqueous solution under sunlight irradiation. Parameters such as irradiation time and doping content were found effective on the photoactivity of pure ZnO and Hf-doped ZnO. The photocatalysis experiments demonstrated that 2Â mol% Hf-ZnO exhibited higher photocatalytic activity as compared to ZnO, ZnO commercial and other hafnium doped ZnO photocatalysts and also revealed that MB was effectively degraded by more than 85% within 120Â min. The enhanced photoactivity might be attributed to effective charge separation and enhanced visible light absorption. It was concluded that the presence of hafnium within ZnO lattice could enhance the photocatalytic oxidation over pure ZnO.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
M. Ahmad, E. Ahmed, Z.L. Hong, Z. Iqbal, N.R. Khalid, T. Abbas, Imran Ahmad, A.M. Elhissi, W. Ahmed,