Figure 2.

HERFD‐XANES spectra of the Cu_I (A) and Cu_Br (B) samples in the as‐prepared state and measured under operando CO₂RR conditions in 0.1 m KHCO₃ after 1 h of CO₂RR at −1.0 V vs. RHE. Reference spectra of bulk Cu, CuI, CuBr, and Cu₂O are also plotted. Linear combination analysis (LCA) of operando HERFD‐XANES spectra of the Cu_I sample measured in the as‐prepared state (C) and during CO₂RR at −1.0 V vs. RHE (D) are shown. The corresponding subspectral components needed to fit the data (metallic Cu, CuI, and Cu₂O) are scaled according to their weighting parameters.