H-assisted CO₂ dissociation on PdPt_(4-/In₂O₃ catalysts: a density functional theory study

Area of Science:

• Catalysis
• Surface Science
• Computational Chemistry

Background:

• Carbon dioxide (CO2) hydrogenation is vital for mitigating greenhouse gas emissions and energy scarcity.
• Understanding CO2 activation and C-O bond cleavage mechanisms is key to efficient reduction.
• The specific role of hydrogen adatoms (*H) in CO2 C-O bond cleavage remains unclear.

Purpose of the Study:

• To investigate H-assisted CO2 dissociation pathways on Pd_xPt_(4-x)/In2O3 (x=0-4) catalysts.
• To elucidate the influence of *H adatoms on the C-O bond cleavage during CO2 reduction.
• To identify optimal catalyst compositions for efficient CO2 hydrogenation.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• Adsorption energies of key intermediates (*H2, *COOH, *HCOO) were computed.
• Two primary H-assisted CO2 dissociation channels were analyzed: COOH-mediated and HCOO-mediated pathways.

Main Results:

• Platinum (Pt) and Palladium (Pd) components influence CO2 hydrogenation and C-O bond cleavage differently.
• The COOH-mediated pathway facilitates C-O bond cleavage, while the HCOO-mediated pathway impedes it.
• Pd3Pt/In2O3 demonstrated superior performance for H-assisted CO2 dissociation.

Conclusions:

• The electronic properties of Pd-Pt bimetals and their interaction with In2O3 are crucial for tuning intermediate stability and reaction barriers.
• Pd3Pt/In2O3 is proposed as a promising catalyst for H-assisted CO2 dissociation.
• This research provides valuable insights for designing advanced catalysts for CO2 hydrogenation.