Subtle tuning of micro-environment in COFs nanoribbons actuates low electricity-consumption photo-assisted Co-electrolysis of methanol and CO ₂

The lower electricity consumption (EC) and higher value-added products are much desired yet still challenging for the development of CO₂ coupling electrocatalytic systems. Herein, we give insight into the inherent nature of the retrenchment of EC by exploring the photo-assisted co-electrolysis of methanol and CO₂ system using a kind of hydroxyl-rich covalent organic frameworks (Dha-COF-Co) with well-tuned pore structure and morphology. Specifically, the hydroxyl induced hydrogen bond interaction in Dha-COF-Co enables to simultaneously regulate the pore microenvironment and nanoribbon morphology of COFs for performance boosting. Notably, the obtained Dha-COF-Co nanoribbon exhibits an overall EC retrenchment of ~41.2% (highest in porous crystalline materials to date) when replacing the anodic OER with MOR in the photo-electrocatalytic MOR-CO₂RR coupling system, as well as superior FE_HCOOH (anode, ~100%) and FE_CO (cathode, >95%) at 1.8 V. Combined theoretical calculations with various characterizations, the vital role of hydroxyl group in both microenvironment and morphology tuning that can facilitate the CO₂RR and MOR kinetics to retrench the EC has been intensively discussed.