Nanoparticle-Single-Atom Tandem Catalyst within a Metal-Organic Framework for Efficient Ethylene Electrosynthesis

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Copper nanoparticles (Cu NPs) are effective for CO2 electroreduction (ECO2R) but face challenges with selectivity, aggregation, and deactivation.
• Developing stable and selective catalysts is crucial for converting CO2 into valuable multicarbon products.

Purpose of the Study:

• To develop a highly selective and robust catalyst for CO2 electroreduction (ECO2R) to multicarbon products.
• To engineer Cu NPs within a metal-organic framework (MOF) host using an in situ encapsulation strategy.

Main Methods:

• One-pot hydrothermal synthesis of MOF-encapsulated Cu NPs with tin (Sn) additives.
• Characterization of Cu NP size modulation and Sn single atoms (SAs) formation.
• Electrochemical testing to evaluate CO2 reduction performance and selectivity.
• In situ infrared spectroscopy and theoretical simulations to elucidate reaction mechanisms.

Main Results:

• The optimized catalyst achieved a 64% Faradaic efficiency for CO2 to ethylene (C2H4).
• Sn SAs modulated Cu NP growth and acted as active sites for CO generation, facilitating C-C coupling via a tandem mechanism.
• Sn SAs enhanced electron transfer to Cu NPs, stabilizing intermediates and lowering activation energy barriers.

Conclusions:

• The MOF encapsulation strategy with Sn SAs provides a novel approach for designing advanced CO2 reduction reaction (CO2RR) catalysts.
• This atomic- and nanoscale design enhances catalyst selectivity, stability, and efficiency for CO2 conversion.
• The tandem mechanism involving Sn SAs and Cu NPs is key to promoting C-C coupling for multicarbon product formation.