A salt induced gelatin crosslinking strategy to prepare Fe-N doped aligned porous carbon for efficient oxygen reduction reaction catalysts and high-performance supercapacitors

Abstract

The preparation of low-cost, high-efficiency and stable oxygen reduction reaction (ORR) catalysts is highly anticipated but remains a challenge. Herein, a novel strategy of CaCl2 solution inducing gelatin crosslinking and acting as aligned pore template was put forward for preparation of Fe-N doped aligned hierarchical porous carbon. Furthermore, the microtopography and length of aligned pore can be controlled by adding NaCl solution. The prepared catalyst exhibited short-range aligned honeycomb hierarchical porous structure with large specific surface area and highly homogeneous distribution of Fe-Nx active sites (Fe-NHHPC-900). Notably, in addition to excellent durability in the alkaline electrolyte, Fe-NHHPC-900 possessed excellent ORR performance with positive half-wave potential of 0.86 V, superior to commercial Pt/C catalysts. As electrode materials of supercapacitors, Fe-NHHPC-900 also displayed a high specific capacitance, excellent rate performance and excellent stability. This work also proved that the unique aligned porous structure can effectively optimize catalyst activity and improve supercapacitor performance.