Pd as a reduction promoter for TiO2: Oxygen and hydrogen transport at 2D and 3D Pd interfaces with TiO2 monitored by TPR, operando 1H NMR and CO oxidation studies

Yarar, Melis
Bouzani, Asmae
Üner, Deniz
© 2022Ambient temperature reduction of TiO2 surface was observed through hydrogen spillover from Pd nanoparticles with a hydrogen consumption stoichiometry of 1.4 H2:Pd up to ≤2 wt%Pd loading. This behavior was attributed to the formation of nanoparticles exhibiting 2D behavior for ≤2 wt%Pd loading. The 2D behavior of Pd nanoparticles were further confirmed from the relative abundance of metallic Pd in 3D, deduced from hydrogen stoichiometry of β-PdHx. EPR revealed oxygen vacancy formation, operando NMR revealed facile hydrogen spillover, and CO oxidation reaction rates systematically increased for Pd ≤ 2 wt%, indicating facile exchange of hydrogen and oxygen at 2D Pd/TiO2 interfaces.
Catalysis Communications


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Citation Formats
M. Yarar, A. Bouzani, and D. Üner, “Pd as a reduction promoter for TiO2: Oxygen and hydrogen transport at 2D and 3D Pd interfaces with TiO2 monitored by TPR, operando 1H NMR and CO oxidation studies,” Catalysis Communications, vol. 174, pp. 0–0, 2023, Accessed: 00, 2023. [Online]. Available: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85143864348&origin=inward.