This study reports on characterization and photoactivity of nanostructured TiO2 samples, which havebeen permanently densified under high pressures, up to 2.1 GPa. Commercial Mirkat 211 anatase has beenused as a benchmark sample, in order to investigate the effect of unidirectional high pressure on structural,optical and photocatalytic properties of TiO2. Vibrational Raman spectroscopy shows that the treatmentdoes not cause transitions among the different crystalline phases of titanium dioxide. UV-vis diffusereflectance spectra reveal that increasing pressure gives rise to a shift of the absorption onset towardshigher wavelength enhancing the photoactivity under visible radiation. Samples are also photo-electrochemicallycharacterized and tested in the gas phase with partial oxidation of ethanol to acetaldehydeunder visible irradiation. Compaction up to 0.8 GPa depresses both the alcohol conversion and the aldehydeyield, while samples treated under higher pressures show enhanced characteristics of conversioncompared to the pristine material. Moreover, promising results in the reduction of CO2 are also obtainedunder UV-visible radiation.
|Numero di pagine||9|
|Rivista||PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES|
|Stato di pubblicazione||Published - 2015|
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