Chitosan-derived N-self-doped Pt/C as stable electrocatalysts for the oxygen reduction

Among the currently studied nitrogen-doped Pt-C catalysts, the environmental friendliness of the nitrogen source and the stability of Pt-C catalysts for fuel cells are urgent issues to be solved. In this study, nitrogen-doped platinum-based catalyst (CSC/BP-Pt) with excellent stability for the ORR is prepared by a self-doping method based on chitosan (CS), a green biomass material with both nitrogen and carbon sources, in combination with conductive carbon black (BP2000). Finally, the N content of the catalyst is as high as 5.8 wt%, which is higher than most comparable catalysts (3–5 wt%). And electrochemical tests show that the CSC/BP-Pt electrochemical active surface area (ECSA) = 154.1 m2/gPt, half-wave potential (E1/2 = 0.85 VRHE) has a better electrochemical performance than the commercial Pt/C (20 wt%), while the half-wave potential is reduced at 10,000 cycles of cyclic voltammetry with almost no attenuation (only 7 mVcompared to 31 mV of Pt/C). Besides, possible mechanisms to improve the activity and stability of CSC/BP-Pt are preliminarily proposed.