Revista Historia Viva Em Pdf Download BETTER
Revista Historia Viva Em Pdf Download
História Viva Apareceu – Compiladora
Páginas e Books de História da Universidade Federal do ABC, 2008-2009. Revista História Viva Em Pdf Download. de História. HISTória VIVA Revista de História.
Revista História Viva Em Pdf Download
Enhancing the intrinsic photocatalytic activities of TiO2-ZrO2-Phen by doping with Nb, Ta, or W.
TiO2-ZrO2-Phen show enhanced light-induced photocatalytic activities for degradation of organic pollutants compared to the neat TiO2-Phen. By using X-ray photoelectron spectroscopy, Nb, Ta, or W-doped TiO2-ZrO2-Phen samples were prepared and characterized. The X-ray diffraction analysis and Raman spectra revealed that the anatase-to-rutile transformation of TiO2-ZrO2-Phen was suppressed by doping with Nb, Ta, or W. Based on the X-ray absorption near edge structure spectra, the Nb, Ta, or W concentrations in the doped TiO2-ZrO2-Phen were 6, 1, and 1 wt%, respectively. Nb or Ta doping significantly inhibited the recombination rate of photogenerated electron-hole pairs and thus enhanced the photocatalytic activities, whereas W doping did not show a significant effect. However, the deactivation rates of the doped and undoped TiO2-ZrO2-Phen samples were similar. The photoluminescence spectra of the Nb-doped TiO2-ZrO2-Phen samples showed significant quenching of the lowest energy (near-band-edge) emission band due to a charge transfer from the Nb dopants to the TiO2-Phen system. Furthermore, the Nb doping resulted in preferential formation of Ti-Nb bonds in the undoped TiO2-ZrO2-Phen, which were not formed in the Nb-doped TiO2-ZrO2-Phen. The preferential formation of Ti-Nb bonds has been proposed to be