Enhancing electrochemical CO<sub>2</sub> reduction performance through surface modification of Ag catalyst with styrene-based ionomers
발표자
()
초록
내용
Implementing ionomers as binders in electrochemical CO2 reduction (CO2R) can suppress H2 evolution reaction (HER) by limiting the accessibility of H2O relative to CO2 near catalyst surface.1 Here, we synthesized a series of styrene-based statistical copolymers with different molecular weights (Mn) and functionalized them with various 1-alkylimidazolium salts. The salts with different alkyl side-chain lengths (N) were employed to control the hydrophobicity of each ionomer systematically. These materials were then implemented as binders for Ag-based catalysts in a two-compartment electrochemical cell to study the effect of the binder design on the CO2R performance. Examining faradaic efficiencies (FEs) and partial current densities of CO, H2, and HCOO– reveals that increasing N from 1 to 16 suppressed HER and reduced the FE for HER from 72% to 3% at –1.22 V (vs. RHE) but had little impact on the CO and HCOO– production. References: (1) J. Am. Chem. Soc., 143, 14712 (2021).