Synergistic Heterostructure Catalyst for Enhanced CO₂-to-C2 Conversion and High-Performance Aqueous Zn-CO₂ Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Carbon dioxide (CO2) conversion is crucial for sustainability.
• Developing efficient catalysts for CO2 reduction to higher-value products is a key challenge.
• Aqueous batteries offer a promising platform for energy storage and CO2 utilization.

Purpose of the Study:

• To investigate the synergistic effects of CuO and SnO2 in a heterostructure catalyst (CuO@SnO2).
• To enhance the conversion of C1 CO2 reduction products to C2 products, specifically ethanol.
• To apply the developed catalyst in high-performance aqueous Zinc-CO2 batteries.

Main Methods:

• Fabrication of a CuO@SnO2 heterostructure catalyst.
• Electrochemical characterization of the catalyst for CO2 reduction.
• Assembly and testing of a flow-type aqueous Zn-CO2 battery system.

Main Results:

• The CuO@SnO2 catalyst significantly improved Faradaic efficiency (FE) for ethanol production from 12.5% to 41.8%.
• The catalyst shifted selectivity from C1 to C2 products during CO2 reduction.
• The aqueous Zn-CO2 battery achieved an ultrahigh power density of 6.5 mW cm-2 and a discharge voltage of 0.9 V.
• Stable operation over 140 cycles demonstrated excellent catalyst reversibility and durability.
• A FE of 36.86% for ethanol production was achieved during battery discharge.

Conclusions:

• The synergistic interaction between CuO and SnO2 is vital for optimizing CO2 conversion and ethanol production.
• The CuO@SnO2 catalyst demonstrates exceptional performance in dual-function energy storage and CO2 utilization systems.
• This research paves the way for industrial-scale applications in renewable energy generation and sustainable CO2 management.