Selecting the proper doping strategy is essential to controlling the photocatalytic activity of TiO2-based nanomaterials. In this work, we compare impregnation and bulk synthesis methods for feeding titania nanocrystals with either Nb or Ta as transition metal dopant and N as nonmetal codopant. The resulting photocatalytic efficiency was tested toward ethanol degradation under either UV or simulated solar irradiation. Microstructure, morphology, and electronic properties at various length scales were deeply investigated and compared with DFT simulations. Instead, under UV irradiation, impregnated samples performed better than bulk synthesis ones, with Ta-doped powders being more efficient than Nb-doped and undoped TiO2. Under simulated solar irradiation, bulk synthesis Nb-doped materials were the most active ones, while all the impregnated samples were even less performing than the undoped TiO2 reference. On the basis of XPS, EPR, DRS, and XRPD results, such differences were attributed to the bulk synthesis approach producing a more homogeneous distribution of guest dopants within the grains, in conjunction with a higher amount of intrinsic defects (such as O vacancies). Implications of these findings on the engineering of efficient titania photocatalysts are discussed.

Impregnation versus Bulk Synthesis : How the Synthetic Route Affects the Photocatalytic Efficiency of Nb/Ta:N Codoped TiO2 Nanomaterials / L. Rimoldi, C. Ambrosi, G. DI LIBERTO, L. Lo Presti, M. Ceotto, C. Oliva, D. Meroni, S. Cappelli, G. Cappelletti, G. Soliveri, S. Ardizzone. - In: JOURNAL OF PHYSICAL CHEMISTRY. C. - ISSN 1932-7447. - 119:42(2015 Oct 08), pp. 24104-24115. [10.1021/acs.jpcc.5b06827]

Impregnation versus Bulk Synthesis : How the Synthetic Route Affects the Photocatalytic Efficiency of Nb/Ta:N Codoped TiO2 Nanomaterials

L. Rimoldi;G. DI LIBERTO;L. Lo Presti;M. Ceotto;C. Oliva;D. Meroni;S. Cappelli;G. Cappelletti;G. Soliveri;S. Ardizzone
2015

Abstract

Selecting the proper doping strategy is essential to controlling the photocatalytic activity of TiO2-based nanomaterials. In this work, we compare impregnation and bulk synthesis methods for feeding titania nanocrystals with either Nb or Ta as transition metal dopant and N as nonmetal codopant. The resulting photocatalytic efficiency was tested toward ethanol degradation under either UV or simulated solar irradiation. Microstructure, morphology, and electronic properties at various length scales were deeply investigated and compared with DFT simulations. Instead, under UV irradiation, impregnated samples performed better than bulk synthesis ones, with Ta-doped powders being more efficient than Nb-doped and undoped TiO2. Under simulated solar irradiation, bulk synthesis Nb-doped materials were the most active ones, while all the impregnated samples were even less performing than the undoped TiO2 reference. On the basis of XPS, EPR, DRS, and XRPD results, such differences were attributed to the bulk synthesis approach producing a more homogeneous distribution of guest dopants within the grains, in conjunction with a higher amount of intrinsic defects (such as O vacancies). Implications of these findings on the engineering of efficient titania photocatalysts are discussed.
Nanostructured titania; gas phase photocatalysis; Nb:N codoping; Ta:N codoping; Sol-gel synthesis; electron paramagnetic resonance
Settore CHIM/02 - Chimica Fisica
8-ott-2015
Article (author)
File in questo prodotto:
File Dimensione Formato  
MANUSCRIPT_revised.pdf

accesso riservato

Tipologia: Post-print, accepted manuscript ecc. (versione accettata dall'editore)
Dimensione 1.96 MB
Formato Adobe PDF
1.96 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Rimoldi_Ambrosi_Di-Liberto_Lo-Presti_Ceotto_Oliva_Meroni_Cappelli_Cappelletti_Soliveri_Ardizzone_J_Phys_Chem_C_2015_10.1021acs.jpcc.5b06827.pdf

accesso riservato

Tipologia: Post-print, accepted manuscript ecc. (versione accettata dall'editore)
Dimensione 2.06 MB
Formato Adobe PDF
2.06 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
acs.jpcc.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 2.07 MB
Formato Adobe PDF
2.07 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

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/2434/324193
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 38
  • ???jsp.display-item.citation.isi??? 37
social impact