Abstract
To overcome the drawbacks of the single N-doped carbon materials, the further development of dual-heteroatoms (N and S) co-doped electrocatalysts is highly anticipated. Herein, N, S-doping and Fe-based carbon materials were synthesized by pyrolyzing a metal–organic framework (MIL-88) with the addition of N-/N, and S-containing ligands (chitosan and L-Cysteine) in the case of iron salt. The resulting electrocatalyst heat-treated at 850 °C (FeNSC-850) displays superior oxygen reduction reaction (ORR) performances to MIL-88-850, with an overall electron transfer number of 3.97 and a minor yield of HO2-% (<2.6%). In addition to the comparable activity to commercial Pt/C in catalyzing the ORR in alkaline solution, the FeNSC-850 also shows higher stability, with a slight decline in half-wave potential (∆E1/2 = 15 mV) after 5000-cycle scanning of cyclic voltammetry. In view of the multiple Fe-based active sites, the additional S doping within FeNSC-850 creates more FeSx active sites for boosting the ORR performances in alkaline solution.
Funder
National Natural Science Foundation of China
Natural Science Foundation of Inner Mongolia
Subject
Physical and Theoretical Chemistry,Catalysis,General Environmental Science