• • C2+ Faradaic efficiency of 80.4% at 800 mA cm−2: This exceeds typical Cu-based catalysts (often <70% at such high current densities), directly addressing the industrial requirement for high selectivity at ampere-level currents, reducing downstream separation costs.
• • Rate-determining hydrogenation barrier reduced by 0.16 eV: DFT calculations show that Cu(100)/Cu(110) interfaces lower the energy barrier for *CO hydrogenation to *CHO, enabling faster kinetics and higher turnover rates, critical for maintaining performance under industrial load.
• • Kilogram-scale brochantite nanosheet precursors: The synthesis is scalable, producing gram to kilogram quantities, which is essential for transitioning from laboratory to industrial electrolyzer stacks, mitigating supply chain bottlenecks.
• • Operando Raman evidence of sufficient *CO surface coverage: The abundant interfaces sustain high *CO coverage, promoting C–C coupling and suppressing competing hydrogen evolution, as evidenced by the high C2+ selectivity at 800 mA cm−2.