Adsorption and desorption of toluene on nanoporous TiO2/SiO2 prepared by atomic layer deposition (ALD): influence of TiO2 thin film thickness and humidity

作者：Seo Hyun Ook; Kim Dae Han; Kim Kwang Dae; Park Eun Ji; Sim Chae Won; Kim Young Dok^*

来源：Adsorption, 2013, 19(6): 1181-1187.

DOI：10.1007/s10450-013-9550-3

• Toluene adsorption
• TiO2
• SiO2
• Thin film
• Humidity
• Temperature programmed desorption (TPD)

Adsorption and desorption of toluene on bare and TiO2-coated silica with a mean pore size of 15 nm under dry and humid conditions were studied using toluene breakthrough curves and temperature programmed desorption (TPD) of toluene and CO2. Two TiO2/silica samples (either partially or fully covered with TiO2) were prepared with 50 and 200 cycles of TiO2 atomic layer deposition (ALD), respectively. The capacity of silica to adsorb toluene improved significantly with TiO2-thin film coating under dry conditions. However, toluene desorption from the surface due to displacement by water was more pronounced for TiO2-coated samples than bare samples under humid conditions. In TPD experiments, silica with a thinner TiO2 film (50-ALD cycled) had the highest reactivity for toluene oxidation to CO2 both in the absence and presence of water. Toluene adsorption and oxidation reactivity of silica can be controlled by modifying the silica surface with small amount of TiO2 using ALD.

• 出版日期2013-12