Micromonolithic Electrochemical Cells for Sustainable Syngas Production from H₂O and CO₂

The direct conversion of CO₂, preferably from direct air capture (DAC), and H₂O from seawater to syngas by renewable electricity, offers an alternative route toward a sustainable future for the chemical industry. To achieve this ambitious goal, an efficient electrochemical conversion route is preferred. However, high-performance and cost-effective devices for achieving such sustainable production are lacking. Here, we report an innovative micromonolithic solid oxide electrolysis cell (SOEC) device with a productivity of -2.4 A/cm² at 1.4 V and an operational stability of ∼ -1.0 A/cm² (-11.7 A/cm³, 4387 N m³ _syngas/h/m³) for 110 h; this device has an almost 1 order of magnitude greater cost-effectiveness and has substantial environmental benefits compared to conventional tubular and planar designs. The conceptual process design of prospective sustainable electrified syngas production has the potential to achieve 0.1 $/Nm³ _syngas and -0.92 kgCO₂/kg_syngas. Moreover, microstructural sensitivity, three-stage degradation mechanism, and mechanical features of the cell are studied to provide deep insights.