Surface Organo-Iron Chemistry Towards Efficient Reverse Water-Gas Shift Catalysis

Area of Science:

• Catalysis
• Materials Science
• Chemical Engineering

Background:

• The low-temperature reverse water-gas shift (LT-RWGS) is crucial for syngas production and reducing carbon emissions.
• Developing efficient and well-defined catalysts for LT-RWGS remains a significant challenge.

Purpose of the Study:

• To identify the grafting properties of tetramesityldiiron (Fe2Mes4) for designing tailored catalysts.
• To synthesize and characterize a molecular analogue for understanding the grafting mechanism.

Main Methods:

• Synthesis and characterization of a molecular analogue Fe2Mes3OSi(OtBu)3 using X-ray diffraction, 57Fe-Mössbauer, and 1H-NMR spectroscopy.
• Investigating the grafting behavior of tetramesityldiiron on silica surfaces.

Main Results:

• Tetramesityldiiron grafts onto silica via selective displacement of a mesityl ligand, forming Fe2Mes3@SiO2.
• Steric hindrance prevents secondary interactions, leading to well-defined catalyst structures.
• Demonstrated the potential of Fe2Mes4 as a precursor for bimetallic MFe@SiO2 catalysts.

Conclusions:

• Tetramesityldiiron is a versatile precursor for synthesizing highly efficient LT-RWGS and CO2 hydrogenation catalysts.
• The identified grafting mechanism enables the rational design of advanced catalytic materials.