XPS and HR TEM Elucidation of the Diversity of Titania-Supported Single-Site Ir Catalyst Performance in Spin-Selective Propene Hydrogenation.

ABSTRACT: Immobilized [Ir(COD)Cl]₂-Linker/TiO₂ catalysts with linkers containing Py, P(Ph)₂ and N(CH₃)₂ functional groups were prepared. The catalysts were tested via propene hydrogenation with parahydrogen in a temperature range from 40 °C to 120 °C which was monitored via NMR. The catalytic behavior of [Ir(COD)Cl]₂-Linker/TiO₂ is explained on the basis of quantitative and qualitative XPS data analysis performed for the catalysts before and after the reaction at 120 °C. It is shown that the temperature dependence of propene conversion and the enhancement of the NMR signal are explained via a combination of the stabilities of both the linker and immobilized [Ir(COD)Cl]₂ complex. It is demonstrated that the N(CH₃)₂-linker is the most stable at the surface of TiO₂ under used reaction conditions. As a result, only this sample shows a rise in the enhancement of the NMR signal in the 100-120 °C temperature range.

SUBMITTER: Nartova AV 

PROVIDER: S-EPMC10650017 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature