Sulfur-passivated Pt cluster edges on CeO₂ for selective CO₂-to-CO conversion

Area of Science:

• Heterogeneous Catalysis
• Materials Science
• Environmental Chemistry

Background:

• The reverse water-gas shift (RWGS) reaction is key for converting CO2 into valuable chemicals.
• Platinum (Pt)-based catalysts show promise but struggle with CO selectivity and durability at high temperatures due to CO adsorption issues.

Purpose of the Study:

• To develop a Pt-based catalyst with enhanced CO selectivity and stability for the RWGS reaction.
• To address the trade-off between activity, stability, and selectivity in CO2 conversion catalysts.

Main Methods:

• Sulfur (S)-mediated targeted passivation of Pt-CeO2 catalysts.
• In situ/ex situ characterizations and density functional theory (DFT) calculations.
• High-temperature catalytic performance testing at 600°C.

Main Results:

• Optimized Pt-S-CeO2 catalyst demonstrated >95% CO selectivity.
• Achieved a CO production rate of 8.8×10^-5 mol gcat^-1 s^-1.
• Exhibited excellent stability with <10% activity loss over 250 hours.

Conclusions:

• Sulfur incorporation in CeO2 weakens CO adsorption and suppresses methanation.
• The developed catalyst offers a sustainable pathway for CO2 utilization.
• Presents a generalizable strategy for catalyst design in heterogeneous catalysis.