Phosphate modified ceria as a Brønsted acidic/redox multifunctional catalyst
Nelson, Nicholas C.
Manzano, J. Sebastián
Royal Society of Chemistry
Is Version Of
ChemistryAmes National Laboratory
Deposition of trimethylphosphate onto ceria followed by thermal treatment resulted in the formation of surface phosphates with retention of the ceria fluorite structure. The structural and chemical properties of the phosphate-functionalized ceria were studied using 31P solid-state NMR, XPS, zeta titration, ammonia thermal desorption, pyridine adsorption, and model reactions. The introduction of phosphates generated Brønsted acid sites and decreased the number of Lewis acid sites on the surface. The relative amount of Lewis and Brønsted acids can be controlled by the amount of trimethylphosphate used in the synthesis. Upon deposition of Pd, the multifunctional material showed enhanced activity for the hydrogenolysis of eugenol and guaiacol compared to Pd on the unmodified ceria support. This was attributed to the cooperativity between the Lewis acid sites, which activate the substrate for dearomatization, and the redox/Brønsted acid properties, which catalyze hydrogenolysis.
This is a manuscript of an article published as Nelson, Nicholas C., Zhuoran Wang, Pranjali Naik, J. Sebastián Manzano, Marek Pruski, and Igor I. Slowing. "Phosphate modified ceria as a Brønsted acidic/redox multifunctional catalyst." Journal of Materials Chemistry A 5, no. 9 (2017): 4455-4466. DOI: 10.1039/C6TA08703E. Copyright 2017 The Royal Society of Chemistry. Posted with permission.