Figure . High resolution TEM and high angle annular dark field image (HADDF) and EDS map of the catalyst particles after steady state and pulsed electrolysis. the electrolyte for both static and pulsed electrolysis is same: 1 M KOH and 1.5 M NH4OH. For static electrolysis, the electrode applied a chronoamperometry at -1.8 V vs Ag/AgCl for 30 mins. For pulsed electrolysis, the electrode applied a cathodic potential are E ca = 1.8 V for 1s then E an = -0.2 V for 1s. In total, the pulsed condition is conducted 30 min. For static electrolysis, the potential sets as -1.8 V. For pulsed electrolysis, the values for the cathodic time and anodic time are t ca = 1s and tan = 1s, and the cathodic potential are E ca = 1.8 V and E an = -0.4 V to 0.4 V, respectively. Each system was fed with CO2 at a constant flow (10 sccm). The results in line with the results of the ECSA detection, which means the selectivity towards CH4 has some relation with the surface roughness . The highest Faradaic efficiency of CH4 is 0 V in the absence of NH3 and 0.2 V in the presence of the NH3. Each electrolysis conditions were repeated for more than 3 times to determine standard deviations between measurements.