AbstractElectric field‐induced decomposition of ammonia into hydrogen and nitrogen was investigated over CeO2, Fe‐, Ru‐ deposited CeO2, CePO4 and Sr‐doped CePO4, and CeZrO4 in a packed bed down‐flow reactor. The effect of applied current, concentration of ammonia in a feed, and residence time was examined using CeO2 alone. The conversion of ammonia was also studied with respect to a reduction temperature, loading and a type of the deposited metal. The activity results have been analyzed in terms of surface, morphological and electrical characterization of the catalysts. Among metal‐deposited catalysts, ammonia decomposition result at 4 mA was the best for 1 wt % Fe/CeO2 reduced at 550 °C, showing 22 % of conversion with 0.18 mmol of converted ammonia per kJ of energy consumed. The activity of studied Ce‐based catalysts normalized per mass of loaded catalyst showed an accordance in activity‐porosity relation.