Highly Active and Stable Ni/La-Doped Ceria Material for Catalytic CO₂ Reduction by Reverse Water-Gas Shift Reaction

Area of Science:

• Materials Science
• Catalysis
• Chemical Engineering

Background:

• Developing effective catalysts for CO2 conversion is vital for addressing global warming and energy needs.
• The reverse water-gas shift (rWGS) reaction is a key step in valorizing CO2 into useful products.
• Economically viable and high-performance catalysts are essential for industrial applications.

Purpose of the Study:

• To design and synthesize highly efficient catalysts for the CO2 conversion via the rWGS reaction.
• To investigate the structure-activity relationships of Ni/La-doped CeO2 catalysts for CO2 valorization.
• To understand the fundamental mechanisms underlying the catalytic performance.

Main Methods:

• Synthesis of macroporous Ni/La-doped CeO2 catalysts using combustion methods.
• Characterization using X-ray and neutron powder diffraction, Raman spectroscopy, XPS, and electron microscopy.
• Catalytic testing of the rWGS reaction and density functional theory (DFT) calculations.

Main Results:

• Ni/La-doped CeO2 catalysts with optimized Ni and La proportions exhibited unprecedented catalytic performance per unit mass.
• Specific catalyst composition Ni0.07/(Ce0.9La0.1O)0.93 achieved high CO production (58 × 10^-5 molCO·gcat^-1·s^-1) with >99.5% CO selectivity.
• The catalyst demonstrated stability for 100 hours of continuous operation.

Conclusions:

• Optimized Ni/La-doped CeO2 catalysts offer a promising solution for efficient CO2 conversion.
• The study provides fundamental insights into the active sites and reaction mechanisms for CO2 reduction.
• This research lays the groundwork for developing economical and effective catalysts for CO2 valorization.