Abstract
Substituted metal oxides containing ionic species have been attracting a great deal of attention because of their potential ability to reduce the usage of precious metals in heterogeneous catalysts. We investigate Pd-substituted CeO2 for C–H bond activation reactions including the partial oxidation and dry reforming of CH4. This catalyst has been previously studied for CO oxidation, NOx reduction, and the water-gas shift reaction. Pd-substituted CeO2, Ce1–xPdxO2−δ, was prepared as a powder with high surface area and a hollow sphere morphology using ultrasonic spray pyrolysis. The catalysts were extensively characterized using synchrotron X-ray diffraction and other techniques, confirming phase pure samples up to 10 mol % Pd substitution. Ce0.95Pd0.05O2−δ was found to be active for partial oxidation of CH4 around 500 °C and higher. Our studies, including postcatalytic synchrotron diffraction, suggest that the single-phase Ce1–xPdxO2−δ material is not the active species and that catalysis occurs instead over the reduced two-phase Pd0/CeO2. This observation has been further confirmed by verifying the activity of the reduced Pd0/CeO2 catalysts for ethylene hydrogenation, a reaction that is known to require Pd0.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
