Tuning the Electronic Properties of Homoleptic Silver(I) bis-BIAN Complexes towards Efficient Electrocatalytic CO 2 Reduction.

We report herein the preparation and characterization of six readily assembled bis-coordinated homoleptic silver(I) N,N′-bis(arylimino)acenaphthene (BIAN) complexes of general structure [Ag(I)(BIAN)₂]BF₄ and the influence of the electronic properties of the ligand substitution pattern on their performance in electrochemical CO₂ reduction (CO₂R). All the explored catalysts displayed substantial current enhancements in carbon-dioxide-saturated solvents dependent on the ligated BIAN and no significant concurrent H₂ evolution when utilizing 2% H₂O as a proton source. Additionally, preliminary studies, employing a drop-casted ink of 0.4 mg cm⁻² [Ag(I)(4-OMe-BIAN)₂]BF₄ (Ag4) immobilized onto carbon paper gas diffusion electrodes in a flow cell with 1M KHCO₃ aqueous electrolyte, resulted in a propitious Faradaic efficiency of 51% for CO at a current density of 50 mA cm⁻². [ABSTRACT FROM AUTHOR]