Researchers Unveil New Platform for Catalytic Syngas Conversion

Revealing the synergistic interplay of dual active sites on a spinel ZnAl₂O₄ bimetallic oxide for syngas conversion by state-of-the-art solid-state NMR technologies. Credit: DICP

To bridge the gap between different carbon resources and vital chemicals, catalytic syngas conversion is a key pathway. A new platform for this conversion is oxide-zeolite (OXZEO) bifunctional catalysis.

A team of researchers, led by Prof. Hou Guangjin from the Dalian Institute of Chemical Physics (DICP) at the Chinese Academy of Sciences (CAS), has recently discovered the synergistic interplay mechanism of dual active sites on bimetallic oxides. This discovery can lead to more efficient syngas conversion at the atomic level.

The research was recently published in the journal Chem.

The researchers investigated syngas conversion over a representative spinel ZnAl₂O₄ oxide with combined advanced solid-state nuclear magnetic resonance (NMR) technologies. They utilized in-situ NMR method to observe the full process of syngas conversion to methanol over ZnAl₂O₄ catalyst, during which the formate and methoxy species were identified as the key intermediates.

Through a series of double resonance and multi-dimensional correlation NMR experiments, they identified the dual active sites with structure of -Al_IV-OH···Zn_III-. Thus, they proposed the synergistic catalytic mechanism of the dual active sites on ZnAl₂O₄ catalyst for syngas conversion reaction.

Moreover, they elaborated on the dynamic evolution of the reaction intermediates and active sites during the reaction process at an atomic level.

“On one hand, our work exemplifies the increasing capability of solid-state NMR spectroscopy in the study of surface/interface catalysis,” Prof. HOU said. “On the other hand, the current understanding of the active sites and reaction mechanism can bring inspiration to study syngas conversion and CO₂ hydrogenation on other bimetallic oxide systems, providing important guidance for the rational design and modulation of high-efficiency oxide catalysts.”

Reference: “Synergistic interplay of dual active sites on spinel ZnAl2O4 for syngas conversion” by Qiao Han, Pan Gao, Kuizhi Chen, Lixin Liang, Zhenchao Zhao, Xinlong Yao, Dong Xiao, Xiuwen Han and Guangjin Hou, 8 February 2023, Chem.
DOI: 10.1016/j.chempr.2023.01.004