Substrate co-doping modulates electronic metal-support interactions and significantly enhances single-atom catalysis

Area of Science:

• Materials Science
• Catalysis
• Surface Chemistry

Background:

• Transition metal nanoparticles and single atoms on substrates offer efficient catalysis.
• Controlling electronic metal-support interactions (EMSI) is crucial for optimizing catalyst performance.
• Palladium (Pd) adatoms on titanium dioxide (TiO2) are typically inactive catalysts.

Purpose of the Study:

• To investigate methods for enhancing the catalytic activity of single Pd adatoms on TiO2(110).
• To demonstrate the role of metal-nonmetal co-doping in tuning EMSI.
• To understand the mechanism behind enhanced catalytic performance.

Main Methods:

• First-principles calculations were employed to model Pd adatoms on doped TiO2(110) substrates.
• Electronic structure and adsorption/reaction energies were analyzed.
• The correlation between EMSI strength and catalytic activity was examined.

Main Results:

• Co-doping TiO2(110) with specific metal-nonmetal pairs transforms inactive Pd adatoms into effective catalysts.
• Enhanced EMSI significantly improves O2 adsorption and CO oxidation.
• A linear correlation exists between EMSI strength and catalytic activity metrics.
• Co-doping reduces the CO oxidation barrier on Pd monomers to levels comparable to Pd dimers.

Conclusions:

• Purposeful co-doping of substrates can dramatically enhance EMSI, activating otherwise inactive single-atom catalysts.
• This approach offers a pathway for designing cost-effective, single-atom, and nanoscale catalysts.
• The findings provide fundamental insights into EMSI for heterogeneous catalysis.