O-Vacancy Mediated Partially Inverted Ferrospinels for Enhanced Activity in the Sulfuric Acid Decomposition for...

Area of Science:

• Materials Science
• Catalysis
• Chemical Engineering

Background:

• Characterizing tailored Co3O4 spinel catalysts with Fe3+ doping is complex due to surface states and cation diversity.
• Secondary metal doping creates double spinel structures, enhancing catalytic properties through oxygen vacancies.

Purpose of the Study:

• To synthesize and characterize cobalt-rich (FeCo2O4) and iron-rich (CoFe2O4) hybrid spinels.
• To evaluate their performance in sulfuric acid decomposition for hydrogen production.
• To understand the role of metal-support interaction and electronic properties in catalytic activity.

Main Methods:

• Wet impregnation method for spinel synthesis.
• Support over oxidized silicon carbide (SiC-Pretrt) for enhanced metal-support interaction.
• Detailed characterization and density functional theory (DFT) calculations.

Main Results:

• FeCo2O4 on SiC-Pretrt demonstrated high catalytic activity (90% conversion at 1173 K) and stability (>100 h).
• The enhanced performance is linked to high Co3+ electronegativity, oxygen vacancies, and strong metal-support interaction.
• DFT calculations corroborated the weakening of S-O bonds by Co3+ electronegativity.

Conclusions:

• Tailored FeCo2O4 spinels on SiC are highly effective bifunctional catalysts for the iodine-sulfur process.
• Optimized electronic properties and oxygen vacancies are key to efficient sulfuric acid decomposition.
• This study provides insights into designing advanced catalysts for hydrogen production.