Figure 2.

Operando Raman spectroscopy data on Cu₂O nanocubes during CO₂RR. (a) Raman spectra of Cu₂O nanocubes acquired during CO₂RR for potentials ranging from the OCP to −1.2 V_RHE. (b) Zoom-in spectra of the restricted rotation of adsorbed CO (P1) and Cu–CO stretching (P2) from −0.4 to −1.2 V_RHE. (c) Potential-dependent intensity ratio of P2 to P1. The error bars were obtained as standard deviation (see the Supporting Information for details). All electrochemical experiments were conducted in 0.1 M KHCO₃, and the electrode potentials are given vs the RHE.