Stabilization of Cu⁺ via Strong Electronic Interaction for Selective and Stable CO₂ Electroreduction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Copper oxide-based materials are effective electrocatalysts for carbon dioxide reduction (CO₂ RR).
• Stabilizing Cu⁺ species in copper oxides is crucial for high CO₂ RR activity and selectivity.
• Understanding the role of Cu⁺ is key to designing advanced CO₂ RR catalysts.

Purpose of the Study:

• To stabilize Cu⁺ species in copper(I) oxide (Cu₂O) nanoparticles using hexagonal boron nitride (h-BN) nanosheets.
• To investigate the impact of h-BN decoration on the CO₂ RR performance of Cu₂O.
• To elucidate the mechanism behind the enhanced catalytic activity and stability.

Main Methods:

• Synthesis of Cu₂O nanoparticles decorated with h-BN nanosheets (Cu₂O-BN).
• Electrocatalytic CO₂ reduction (CO₂ RR) experiments comparing Cu₂O-BN with bare Cu₂O.
• Experimental and theoretical studies (e.g., electronic structure analysis) to probe interactions between Cu₂O and h-BN.

Main Results:

• The Cu₂O-BN catalyst showed a 1.62-fold increase in the C₂H₄/CO ratio compared to Cu₂O.
• Strong electronic interactions between Cu₂O and h-BN were confirmed, strengthening Cu-O bonds.
• Electrophilic h-BN protected Cu⁺ from electron attack, enhancing stability during electrolysis and improving C₂ product selectivity.

Conclusions:

• Decorating Cu₂O with h-BN effectively stabilizes Cu⁺ species, leading to improved CO₂ RR performance.
• The electronic interactions between Cu₂O and h-BN are critical for catalyst stability and selectivity.
• This work provides insights into metal-valence-state-dependent selectivity, guiding the design of novel electrocatalysts.