A porous FeO_x, N co-doped carbon material as efficient catalyst toward oxygen reduction reaction in both alkaline and acidic electrolytes

To replace the precious metal ORR (oxygen reduction reaction) electrocatalysts, many TM (transition metal) and N-doped carbon composites have been proposed in last decade and acquire a rapid development as the promising non-precious metal catalysts. Herein, Ketjenblack carbon (KB) is adopted as the precursor and fully mixed with the polymeric ionic liquid (PIL) of HvimNO₃ and Fe(NO₃)₃. This mixture is thermally calcinated into a porous Fe, N co-doped carbon material denoted as the FeO_x-N/C at 900 °C. Due to that the PIL of HvimNO₃ can strongly combine and disperse Fe³⁺ ions, and NO₃⁻ will thermally pyrolysis to form the porous structure, the FeO_x-N/C catalyst displays high electrocatalytic activity toward ORR in both 0.1 M KOH and 0.5 M H₂SO₄ electrolytes. Subsequently, the FeO_x-N/C is used as the catalyst to assemble a zinc-air battery (ZAB) exhibiting a peak power density of 185 mW·cm⁻². Consequently, the superior electrocatalytic activity, wide pH range, and facile preparation approach jointly make the FeO_x-N/C a promising electrocatalyst for the fuel cell and metal-air battery in the future.