Tuesday, November 9, 2010: 4:39 PM
251 C Room (Salt Palace Convention Center)
Platinum (Pt) nanoparticles were deposited on TiO2 P-25 photocatalyst powders as well as TiO2 films using the atomic layer deposition (ALD) method to increase the TiO2 photocatalytic activity. The TiO2 films were coated using the ALD method with TiCl4 and H2O2 as precursors. The Pt ALD was carried out by alternatively exposing the substrate to Methylcyclopentadienyl-(trimethyl) Platinum(IV) (MeCpPtMe3) and oxygen and the operation temperature was ranged from 150 - 400°C. The reaction mechanism of the early stage of Pt ALD was studied and the dependence of the reaction temperature was explored. The low temperature limit for the Pt ALD is approximately 200°C. Methylene blue decomposition behavior was investigated to study the improve effect on the photoactivity of TiO2 caused by Pt modification. After the ALD process, the samples were calcined at 400°C and the photoactivity was tested for samples both before and after the calcination treatment. The degradation pathway of methylene blue was also studied to better understand the Pt modification mechanism to the TiO2 photoactivity.