Highly Efficient Oxygen Reduction Reaction Fe-N-C Cathode in Long-durable Direct Glycol Fuel Cells

The oxygen reduction reaction in direct glycol fuel cells heavily relies on noble metal-based electrocatalysts.In this work,novel Pt group metal-free catalysts based on porous Fe-N-C materials are successfully synthesized as catalysts with high activity and durability for the cathode oxygen reduction reaction(ORR).Through the encapsulation of NH_(4)SCN salt,the surface elements and pore structure of the catalyst are effectively changed,and the active sites of Fe effectively are increased.The half-wave potential of the best Fe-N-C catalyst was-0.02 V vs.Hg/HgO in an alkaline environment.The porous Fe-N-C catalyst possesses a large specific surface area(1158 m^(2)/g)and shows good activity and tolerance to glycol.The direct glycol fuel cell with the Fe-N-C cathode achieved a maximum power density of 62.2 mW/cm^(2) with 4 mol/L KOH and 4 mol/L glycol solution at 25°C and maintained discharge for more than 250 h at a 50 A/cm^(2) current density.