Study of TiO2 anatase nano and microstructures with dominant {001} facets for NO oxidation

Introduction: TiO2 anatase nanoplates and hollow microspheres were fabricated by a solvothermal-hydrothermal method using titanium isopropoxide as a titanium precursor and hydrofluoric acid as a capping agent in order to enhance the formation of the {001} crystal facets of the anatase nanocrystals. Methods: These different morphological structures of TiO2 anatase can be achieved by only changing the solvent, keeping the amount of the precursor and of the capping agent identical during the solvothermal-hydrothermal process. Results and discussion: After calcination of the samples, the adsorbed fluoride atoms on the {001} crystal facets of the TiO2 anatase nanocrystals were completely removed from their surface according to XPS analysis. The calcined TiO2 anatase structures were higher crystallized and the specific surface area of the catalysts increased, enhancing their photocatalytic activity in comparison to the non-calcined TiO2 anatase structures. All TiO2 anatase samples with adsorbed as well as non-adsorbed fluoride atoms on their {001} crystal facets, exhibited a higher photonic efficiency than Degussa P25, which was used as a reference. Conclusion: The fluoride free TiO2 anatase nanoplates exhibited the best photocatalytic activity in oxidizing the NO gas to NO2 and NO3-. © 2012 Springer-Verlag

Persianisms: the Achaemenid Court in Greek art, 380-330 BCE

The Persians held sway over the Greek imagination for more than 200 years. The image of Persia shifted in that time from xenophobic hostility, caused through fear of the encroaching presence of the Persian empire, through to curious acceptance of its dominance. Much study has been given to the formative decades of the construction of the Persian “Other” in Greek art, but the fourth-century image of Persia has remained relatively unexplored. This paper demonstrates how Greek artists of the period 380–330 BCE fixated on the life and accomplishments of the court of the Achaemenid Great Kings and argues that instead of offering an orientalist clichéd view of Persian life, it attempted to understand and disseminate bone fide Iranian images of court society