Selective CO₂-to-C₂H₆ photoconversion over electron-rich Au anchored on In₂O₃ nanosheets

Area of Science:

• Materials Science
• Catalysis
• Photochemistry

Background:

• The photoreduction of carbon dioxide (CO2) is crucial for sustainable energy.
• Developing efficient catalysts for CO2 conversion remains a challenge.
• Selective production of valuable hydrocarbons like ethane (C2H6) is highly desirable.

Purpose of the Study:

• To investigate the effect of electron-rich gold (Au) nanoparticles anchored on indium oxide (In2O3) nanosheets for CO2 photoreduction.
• To understand the catalytic mechanism and thermodynamics of the C-C coupling step.
• To achieve high selectivity and efficiency in producing ethane from CO2.

Main Methods:

• Synthesis of Au-In2O3 nanosheet heterostructures.
• Characterization of the catalyst's electronic and structural properties.
• Photocatalytic experiments for CO2 reduction to C2H6 under simulated solar irradiation.

Main Results:

• Anchoring electron-rich Au on In2O3 nanosheets inverted the C-C coupling thermodynamics from 0.82 eV to -1.42 eV.
• This modification significantly promoted the formation of the key *OCCO intermediate.
• Achieved 85.1% electron selectivity for C2H6 production with an evolution rate of 46.3 µmol g-1 h-1.

Conclusions:

• Electron-rich Au/In2O3 nanosheets are highly effective photocatalysts for selective CO2 reduction to C2H6.
• The inverted C-C coupling thermodynamics are key to enhancing the formation of the *OCCO intermediate.
• This catalytic system offers a promising pathway for efficient and selective solar fuel production from CO2.