The industrial deployment of electrochemical CO₂ reduction is no longer limited only by catalyst activity, but by the ability to maintain selectivity, stability and energy efficiency while gas transport, water management, ion crossover and pressure gradients evolve with electrode area. These challenges become even more critical for integrated CO₂ capture–conversion schemes, where captured or CO₂-rich streams could reduce separation costs but impose additional constraints on electrolyte compatibility, membrane operation and reactor design.[1]

Here, we present a scalable Cu-based gas-diffusion-electrode platform that provides the electrochemical and engineering basis for translating CO₂ electrolysis toward captured-stream syngas production. CRM-lean Cu₂O/SnO₂-derived catalytic layers were fabricated by scalable spray coating and integrated into flow and zero-gap electrolyzer architectures. The platform was evaluated across active areas of 5, 25 and 120 cm², with ongoing scale-up toward 500 cm², reaching current densities up to 500 mA cm⁻². By tuning catalyst-layer architecture, membrane/ionomer pairing, electrolyte composition and operating current density, the product distribution was directed toward CO-rich syngas and formate as complementary C1 routes, with Faradaic efficiencies toward syngas up to 80%.[2-3]

Rather than focusing only on peak performance, this work identifies the operational bottlenecks that govern scalability. Polarization curves, online gas analysis and Faradaic-efficiency mapping were combined to distinguish ohmic losses, flooding onset, CO₂ starvation, membrane dehydration and catalyst-layer inhomogeneity. Post-operation SEM, TEM, XRD and ICP analyses were coupled with COMSOL-based multiphysics modelling to identify transport and pressure-management limitations and guide electrode and cell redesign.[4]

This work therefore moves beyond performance demonstration and delivers scale-up criteria for stable CO₂ electrolysis: reproducible catalyst-layer manufacturing, controlled triple-phase-boundary formation, membrane/ionomer matching, and diagnostic protocols that connect voltage evolution with product selectivity. The resulting platform provides a concrete bridge between purified-CO₂ electrolysis and integrated capture–conversion concepts based on amine or ionic-liquid media, opening a pathway toward decentralized syngas production from industrially relevant CO₂ streams.