A Complementary Experimental and Theoretical Approach for Probing the Surface Functionalization of ZnO with Molecular Catalyst Linkers

Advanced Materials Interfaces, vol. 10

Abstract

Abstract The application of ZnO materials as solid‐state supports for molecular heterogeneous catalysis is contingent on the functionalization of the ZnO surface with stable self‐assembled monolayers (SAMs) of catalyst linker molecules. Herein, experimental and theoretical methods are used to study SAMs of azide‐terminated molecular catalyst linkers with two different anchor groups (silane and thiol) on poly and monocrystalline (0001, ) ZnO surfaces. Angle‐resolved and temperature‐dependent X‐ray photoelectron spectroscopy (XPS) is used to study SAM binding modes, thermal stabilities, and coverages. The binding strengths and atomistic ordering of the SAMs are determined via atom‐probe tomography (APT). Density functional theory (DFT) and ab initio molecular dynamics (AIMD) calculations provide insights on the influence of the ZnO surface polarity on the interaction affinity and conformational behavior of the SAMs. The investigations show that SAMs based on 3‐azidopropyltriethoxysilane possess a higher binding strength and thermal stability than the corresponding thiol. SAM surface coverage is strongly influenced by the surface polarity of ZnO, and the highest coverage is observed on the polycrystalline surface. To demonstrate the applicability of linker‐modified polycrystalline ZnO as a catalyst support, a chiral Rh diene complex is immobilized on the azide‐terminal of the SAM and its coverage is evaluated via XPS.

Authors 10

1. Shravan R. Kousik

   University of Stuttgart

   Affiliation as printed

   Institute for Materials Science University of Stuttgart Heisenbergstraße 3 70569 Stuttgart Germany

2. Helena Solodenko

   University of Stuttgart

   Affiliation as printed

   Chair of Material Physics Institute for Materials Science University of Stuttgart Heisenbergstraße 3 70569 Stuttgart Germany

3. Azade YazdanYar

   University of Stuttgart

   Affiliation as printed

   Institute for Computational Physics University of Stuttgart Allmandring 3 70569 Stuttgart Germany

   Institute for Computational Physics, University of Stuttgart, Allmandring 3, 70569 Stuttgart, Germany

4. Manuel Kirchhof

   University of Stuttgart

   Affiliation as printed

   Institute of Organic Chemistry University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany

   Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany

5. Peter Schützendübe

   Max Planck Institute for Intelligent Systems

   Affiliation as printed

   Max Planck Institute for Intelligent Systems Heisenbergstraße 3 70569 Stuttgart Germany

6. Gunther Richter

   Max Planck Institute for Intelligent Systems

   Affiliation as printed

   Max Planck Institute for Intelligent Systems Heisenbergstraße 3 70569 Stuttgart Germany

7. Sabine Laschat

   University of Stuttgart

   Affiliation as printed

   Institute of Organic Chemistry University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany

   Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany

8. Maria Fyta Aachen Computational Biotechnology

   University of Stuttgart · RWTH Aachen University

   Affiliation as printed

   Computational Biotechnology RWTH Aachen University Worringerweg 3 52074 Aachen Germany

   Institute for Computational Physics University of Stuttgart Allmandring 3 70569 Stuttgart Germany

   Computational Biotechnology, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany

   Institute for Computational Physics, University of Stuttgart, Allmandring 3, 70569 Stuttgart, Germany

9. Joachim Bill

   University of Stuttgart

   Affiliation as printed

   Institute for Materials Science University of Stuttgart Heisenbergstraße 3 70569 Stuttgart Germany

10. Petia P. Atanasova corresponding

    University of Stuttgart

    Affiliation as printed

    Institute for Materials Science University of Stuttgart Heisenbergstraße 3 70569 Stuttgart Germany