Localized mass transport channels for electro-upgrade of dilute CO₂ toward high-yield C₂₊ products.

Abstract

Electrocatalytic upgrade of CO₂ offers a promising approach for recycling of global CO₂ emissions, facilitating the achievement of carbon neutrality. Nevertheless, direct utilization of practical dilute CO₂ is urgently important yet rather difficult, which is hindered by the balance of reaction kinetics and mass transport of CO₂ to the catalytic sites. Herein, we propose coordinating the local environment and active catalyst by constructing covalent organic frameworks (COF) on single-atomic In-doped Cu₂O (In₁@Cu₂O) for a high tolerance of CO₂ inlet concentrations (15% to 100%). The optimized amounts of COF functionalized by the trifluoromethyl group act as the local CO₂/CO diffusion channels via steric confinement effects and C···F electronic effects. Besides, the formation of key intermediates for C₂₊ products is greatly facilitated by the promoted COOH adsorption. Hence, a total current of 81.7 A is realized in a 4 × 100 cm² electrolyzer stack with over 770 mmol/h C₂₊ products at an inlet of dilute CO₂. Such a electrode architecture sheds light on the dilute CO₂ electrolysis at the potential industrial scale.