Modulating Electron Transfer between Pt and MOF Support through Pd Doping Promotes Nanozyme Catalytic Efficiency

Area of Science:

• Materials Science
• Nanotechnology
• Catalysis

Background:

• Electron transfer significantly influences nanozyme catalytic activity, but optimal levels remain debated.
• Controlling electron transfer is crucial for enhancing nanozyme performance.

Purpose of the Study:

• To investigate the effect of electron transfer tuning on nanozyme catalytic activity.
• To introduce palladium (Pd) doping as a strategy to regulate electron transfer in platinum (Pt) and ZIF-8 nanozymes (PtPd@ZIF-8).

Main Methods:

• Synthesized PtPd@ZIF-8 nanozymes with varying Pd doping concentrations.
• Analyzed the electron transfer number and its correlation with catalytic activity.
• Investigated the mechanism using d-band center analysis and intermediate adsorption studies.
• Developed a nanozyme-based immunoassay for zearalenone detection.

Main Results:

• A volcano-shaped relationship was observed between electron transfer number and catalytic activity, with Pt4Pd1@ZIF-8 showing peak activity.
• Increased electron transfer enhanced Pt d-band center, improving *O adsorption but hindering desorption at higher levels.
• The optimized nanozyme achieved a zearalenone detection limit of 0.01 μg/L in an immunoassay, a sixfold improvement over traditional methods.

Conclusions:

• Electron transfer plays a critical role in nanozyme catalysis, with an optimal range for activity.
• Pd doping effectively regulates electron transfer and enhances nanozyme catalytic performance.
• The developed nanozyme-based immunoassay offers superior sensitivity for zearalenone detection.