Recently, simultaneously upgrading the greenhouse gas CO₂ and underutilized ethane has introduced opportunities for synthesizing value-added industrial feedstocks. Depending on the selective bond cleavage in ethane, syngas (CO and H₂) or ethylene can be produced via the dry reforming (C–C bond scission) and oxidative dehydrogenation (C–H bond scission) pathways, respectively. However, it remains challenging to identify and develop active sites responsible for the selective bond cleavage in ethane due to the structural and mechanistic complexities over supported catalysts. Herein, the ethane-CO₂ reaction over CeO₂-supported catalysts was investigated to unravel the functions of distinct interfacial sites by combining kinetic measurements with in situ characterization and theoretical calculations: the Pd/CeO_x interface is responsible for supplying reactive oxygen species; electron-deficient oxygen species on Pd surface boosts the non-selective bond scission to produce syngas; electron-enriched oxygen in the FeO_x/Pd interface enhances the selective scission of the C–H bond to yield ethylene. This work identifies opportunities for using different interfacial structures in selectively upgrading abundant shale gas while mitigating greenhouse gas CO₂.

<b>Figure 1.</b> Yield of C<sub>2</sub>H<sub>4</sub> and CO over different CeO<sub>2</sub>-supported catalysts at 873 K and atmospheric pressure.

Figure 1. Yield of C₂H₄ and CO over different CeO₂-supported catalysts at 873 K and atmospheric pressure.

<b>Figure 2.</b> Bader charge analysis of oxygen and contours of charge density on different representative configurations.

Figure 2. Bader charge analysis of oxygen and contours of charge density on different representative configurations.

Dr. Shyam Kattel

Assistant Professor, Florida A&amp;M University

Appearances

Assistant Professor, Florida A&M University