Thermal and photon effects on the reaction of H2 and O2 to water over Ag–Pd/TiO2
Wahab, A.K. / Nadeem, M.A. / Idriss, H. (2022)
International Journal of Hydrogen Energy, 2022, doi.org/10.1016/j.ijhydene.2022.09.153, in press
- Date: Oktober 2022
The reaction of H2 and O2 to water are studied over a Ag–Pd/TiO2 anatase catalyst, under dark and photo-irradiation conditions in the gas and liquid phases. The catalyst consisted of metal particles of mean size of ca.1 nm dispersed over 10–15 nm TiO2 particles. Kinetic parameters including order of reaction (n), rate constant (k), and activation energy (Ea), were evaluated. Ea for the thermal reaction was found to be 49-47 kJ mol−1. The oxidation reaction rate constant was found to be ca. 3 times higher in the presence of photons when compared to dark reaction at room temperature. The overall quantum yield of the reaction in the slurry phase was found to be 0.09. Considering the number of metal particles on TiO2, the photon yield per metal particle was found to be 0.16. A possible explanation of the changes in kinetics with respect to experimental conditions is given.