Dual-Single-Atom Catalyst with Aptamer-Engineered Confined Reactive Milieu for Spatiotemporally Controlled Selective...

Area of Science:

• Heterogeneous catalysis
• Biomimetic materials science
• Nanotechnology

Background:

• Controlling short-lived reactive intermediates is crucial for efficient heterogeneous catalysis.
• Non-selective diffusion limits catalyst performance in complex reaction media.
• Enzymatic compartmentalization offers a model for precise chemical control.

Purpose of the Study:

• To develop an aptamer-functionalized Au-Fe dual-single-atom catalyst (Apt-Au1-Fe1/NC) for precise spatiotemporal control of reactive intermediates.
• To mimic enzymatic precision by integrating atomically dispersed active sites with molecular recognition elements.
• To decouple catalytic activity from selectivity in complex chemical environments.

Main Methods:

• Design and synthesis of an aptamer-functionalized Au-Fe dual-single-atom catalyst supported on nitrogen-doped carbon (Apt-Au1-Fe1/NC).
• Characterization of the catalyst's structure, including atomically dispersed Au-Fe sites and aptamer functionalization.
• Investigation of the oxygen reduction reaction (ORR) pathway and selectivity using electrochemical methods and mechanistic studies.

Main Results:

• The Apt-Au1-Fe1/NC catalyst achieved a highly selective 3-electron ORR pathway with a lowered energy barrier.
• Exceptional selectivity (87.0%-92.6%) for specific targets was observed, with non-specific mineralization suppressed below 5.3%.
• Synergistic electronic interactions between Au-Fe sites and aptamer-mediated substrate pre-enrichment were confirmed.

Conclusions:

• The developed catalyst design creates a "smart reactive pocket" that enhances selectivity and efficiency.
• Biological recognition-based spatial constraints on inorganic active centers enable precision chemical conversion.
• This work establishes a universal paradigm for decoupling activity from selectivity in catalysis.