Fig. 2: Deactivation mechanism of noble metals under CP-EGOR.

a EGOR current density (j) over time (green solid line) measured at +1.43 V during in situ Raman spectrum collection using an Au/Ti electrode. b In situ Raman spectra collected at different time during the I-t measurement in (a). The a.u. of the ordinate represents arbitrary units. The acquisition time for each spectrum was 20 s. The capital letters in (a) and (b) represent the collection points of Raman spectra. c The Au L₃-edge XANES spectra and (d) EXAFS spectra of an Au/Ti electrode collected at +0.43 V and +1.33 V, compared with reference samples (gold oxide and Au metal). Electrolyte: 1 M KOH with 0.3 M EG. e EGOR current density over time measured with EG injection at different time: 0 s (black dashed line), 150 s (red solid line), and 1800 s (purple solid line). A sample of Pd/NF-10 was initially biased at +1.23 V in a pure 1 M KOH solution, and EG was then quickly injected under vigorous stirring at different time to achieve a concentration of 0.3 M. Insets show the details of the current change upon EG injection. f Schematic illustration of the EGOR deactivation over noble metal (M=Pd, Pt, Au) catalyst during CP electrolysis. Source data are provided as a Source Data file.