School of Earth, Environmental, & Marine Sciences Faculty Publications and Presentations

Document Type

Article

Publication Date

2-2025

Abstract

The selectivity of acetylene hydrogenation by the Rh single-atom catalyst (SAC) supported on HY zeolite was investigated using density functional theory (DFT) and a 5/83T quantum mechanics/molecular mechanics (QM/MM) embedded cluster model. The calculated activation barrier (ΔG‡) for the oxidative addition of dihydrogen to the Rh metal center (15.9 kcal/mol) is lower in energy than that for the σ-bond metathesis of dihydrogen to the Rh—C bond (22.7 kcal/mol) and the Rh—O bond (28.4 kcal/mol). The activation barriers of the oxidative addition of subsequent dihydrogen molecules are significantly higher than that of the oxidative addition of the first dihydrogen molecule. These findings align with the experimentally observed activity and selectivity of the atomically dispersed Rh catalyst supported on HY zeolite. Natural bond orbital (NBO), molecular orbital (MO) and fuzzy bond order analyses were used to examine the interaction between the Rh metal center and acetylene versus ethylene ligands. The occupancies of the Rh lone pairs, π-bonding and π*-antibonding orbitals of acetylene and ethylene are consistent with the expected stronger interaction between the Rh metal center and acetylene compared to ethylene on the HY zeolite support.

Comments

© 2025 The Author(s). ChemPhysChem published by Wiley-VCH GmbH

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Publication Title

ChemPhysChem

DOI

10.1002/cphc.202400867

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.