This study reports on characterization and photoactivity of nanostructured TiO2 samples, which have been permanently densified under high pressures, up to 2.1 GPa. Commercial Mirkat 211 anatase has been used 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 treatment does not cause transitions among the different crystalline phases of titanium dioxide. UV-vis diffuse reflectance spectra reveal that increasing pressure gives rise to a shift of the absorption onset towards higher wavelength enhancing the photoactivity under visible radiation. Samples are also photo-electrochemically characterized and tested in the gas phase with partial oxidation of ethanol to acetaldehyde under visible irradiation. Compaction up to 0.8 GPa depresses both the alcohol conversion and the aldehyde yield, while samples treated under higher pressures show enhanced characteristics of conversion compared to the pristine material. Moreover, promising results in the reduction of CO2 are also obtained under UV-visible radiation.

Carini, G., Parrino, F., Palmisano, G., Scandura, G., Citro, I., Calogero, G., et al. (2015). Nanostructured anatase TiO2 densified at high pressure as advanced visible light photocatalysts. PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES, 14(9), 1685-1693 [10.1039/c5pp00149h].

Nanostructured anatase TiO2 densified at high pressure as advanced visible light photocatalysts

PARRINO, Francesco;PALMISANO, Giovanni;
2015

Abstract

This study reports on characterization and photoactivity of nanostructured TiO2 samples, which have been permanently densified under high pressures, up to 2.1 GPa. Commercial Mirkat 211 anatase has been used 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 treatment does not cause transitions among the different crystalline phases of titanium dioxide. UV-vis diffuse reflectance spectra reveal that increasing pressure gives rise to a shift of the absorption onset towards higher wavelength enhancing the photoactivity under visible radiation. Samples are also photo-electrochemically characterized and tested in the gas phase with partial oxidation of ethanol to acetaldehyde under visible irradiation. Compaction up to 0.8 GPa depresses both the alcohol conversion and the aldehyde yield, while samples treated under higher pressures show enhanced characteristics of conversion compared to the pristine material. Moreover, promising results in the reduction of CO2 are also obtained under UV-visible radiation.
Settore ING-IND/24 - Principi Di Ingegneria Chimica
Carini, G., Parrino, F., Palmisano, G., Scandura, G., Citro, I., Calogero, G., et al. (2015). Nanostructured anatase TiO2 densified at high pressure as advanced visible light photocatalysts. PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES, 14(9), 1685-1693 [10.1039/c5pp00149h].
File in questo prodotto:
File Dimensione Formato  
carini 1.pdf

Solo gestori archvio

Dimensione 2.51 MB
Formato Adobe PDF
2.51 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10447/177438
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 15
  • ???jsp.display-item.citation.isi??? 15
social impact