Synergistic Heterostructure Catalyst for Enhanced CO ₂ ‐to‐C2 Conversion and High‐Performance Aqueous Zn‐CO ₂ Batteries

This study investigates the synergistic interaction of CuO and SnO₂ in a heterostructure catalyst (CuO@SnO₂) for the conversion of C1 carbon dioxide (CO₂) reduction products to C2 products and its application in high-performance aqueous Zn-CO₂ batteries. This synergistic combination enhances the Faradaic efficiency (FE) for ethanol production from 12.5% to 41.8%, shifting the selectivity from C1 to C2 products. The flow-type aqueous Zn-CO₂ battery exhibits an ultrahigh power density of 6.5 mW cm^-2, demonstrates a high discharge voltage of 0.9 V, and maintains stable operation over 140 cycles, underscoring the catalyst's exceptional reversibility and durability. During battery discharge, the system achieves a FE of 36.86% for ethanol production. These results highlight the pivotal role of the CuO@SnO₂ synergy in optimizing CO₂ conversion efficiency while generating electrical energy. The findings advance the development of dual-function energy storage systems that integrate renewable electricity generation with sustainable CO₂ utilization, paving the way for industrial-scale applications.