Details

Autor(en) / Beteiligte

• Horikoshi, Satoshi
• Matsubara, Akihiro
• Takayama, Sadatsugu
• Sato, Motoyasu
• Sakai, Futoshi
• Kajitani, Masatsugu
• Abe, Masahiko
• Serpone, Nick

Titel

Characterization of microwave effects on metal-oxide materials: Zinc oxide and titanium dioxide

Ist Teil von

• Applied catalysis. B, Environmental, 2009-09, Vol.91 (1-2), p.362-367

Ort / Verlag

Kidlington: Elsevier B.V

Erscheinungsjahr

2009

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Microwave specific effects originating from either the magnetic and/or electric field of the microwaves that may impact the photoactivity of TiO2 and ZnO have been examined in the photodegradation of the 4-chlorophenol toxin. The microwave specific effect(s) that can impact a microwave-assisted and photo-assisted reaction occurring on the surface of ZnO or TiO2 (P-25) particles was (were) examined by comparing the process occurring under rich magnetic field conditions and under magnetic/electric field conditions. The features of the photo-assisted process in the presence of microwaves rich in a magnetic field (H) and an electric field (E) are described on the basis of (i) the degradation dynamics of 4-chlorophenol (4-CP) at ambient temperatures, (ii) the number of OH radicals produced, and (iii) the dielectric properties of the metal oxides (in pellet form). For ZnO, the photoactivity is enhanced by a microwave specific non-thermal (i.e. non-caloric) effect originating from the microwaves’ magnetic field, but decreased by the thermal (i.e. caloric) factor originating from the microwaves’ electric field. Contrary to ZnO, the photoactivity of TiO2 (P-25) was enhanced by the synergistic effect between the magnetic and electric fields of the microwave radiation. Photocorrosion of ZnO in the aqueous dispersions was negligibly small (less than 0.05%) under UV, MW-EH, and UV/MW-EH irradiation conditions.