Fig. 5: In-situ characterization and theoretical calculations.

In-situ FT-IR spectra of commercial Cu under CO₂RR in electrolyte (a) without CA, (b) with CA. a.u. arbitrary units. c Schematic of CO₂RR mechanism and pathway for various single-/multi-carbon products. d ∆G diagram of C–C coupling on Cu(100) and Cu(100)-CA. e COHP analysis of C–O bonding interaction in ^*OC₂H₃ intermediate on Cu(100) (left) and Cu(100)-CA (right). f COHP analysis of Cu–O bonding interaction in ^*OC₂H₃ intermediate on Cu(100) (left) and Cu(100)-CA (right). g Diagram of CA-dominated CO₂-to-C₂H₅OH conversion mechanism over Cu catalyst. Gibbs free energy diagram of ^*OC₂H₃ to C₂H₄ or C₂H₅OH over (h) Cu(100), (i) Cu(100)-CA. j The atomic structure of C–C coupling and C₂H₄/C₂H₅OH formation states on Cu(100)-CA. Color code: grey (C), white (H), red (O), orange (Cu).