fig14

Figure 14. (A) Operando XANES under the open-circuit condition and at potentials ranging from 0.9 to 0.3 V; (B) Operando XANES when the applied potentials were reversed^[62]; (C) The operando Cu K-edge XANES spectra at different voltages. The inset shows the magnified adsorption-edge region; (D) The difference in the location of the main peak and the Cu-N/O coordination number and the intensity difference of the infrared signals at 918 and 1,055 cm^-1 change with applied potentials for Cu-Se DAs during the ORR process^[63]. DAs: Diatomic catalyst; ORR: oxygen reduction reaction; XANES: Near-Edge X-ray Absorption Fine Structures.