The adsorption, thermal reactions, and photochemistry of C2H5I have been studied on TiO2 by Fourier-transformed infrared spectroscopy. C2H5I is adsorbed on TiO2 and remains intact at 35 °C. However, it decomposes to form C2H5O(a) at temperatures below 200 °C in vacuum. It is found that this decomposition process is enhanced by the presence of isolated surface hydroxy groups. In the study of the thermal reaction of C2H5I on TiO2 in a closed IR cell without O2, ethylene is the only gas product detected. However in the presence of O2, in addition to ethylene, H2O, CO and CO2 are generated together with surface species probably derived from the adsorption of another product of acetaldehyde. In the photochemistry of C2H5I on TiO2 in forming surface formate and acetate, which are probably produced via acetaldehyde intermediate, O2 plays an essential role. It is likely that the photoreaction is initiated by O2-, generated from photoelectron capture by adsorbed O2.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry