For in situ IR spectroscopy, the experiments were executed through the use of a custom-designed spectroelectrochemical cell. The carbon cloth was placed in the middle to separate the electrolyte and the gas chambers. Simultaneously, glassy carbon rod was used as the counter electrode and the Ag/AgCl was used as the reference. Each infrared absorption spectrum was acquired by averaging 800 scans and then subtracting from the spectra at open circuit potential. The background spectrum of the catalyst electrode was acquired at open-circuit voltage before each systemic set of measurements, and the measured potential ranges of the electrocoupling reaction were set to 0.4 to -0.4 VAg/AgCl with an interval of 0.2 V.