A self-sponsored doping approach for controllable synthesis of S and N co-doped trimodal-porous structured graphitic carbon electrocatalysts

A facile self-sponsored doping approach is developed to synthesize S and N co-doped trimodal-porous structured graphitic carbon network electrocatalysts. It utilizes a sole precursor (1-allyl-2-thiourea) to realize a precisely controlled co-doping of S and N during a concurrent graphitic carbon growth process by simple control of the pyrolysis temperature. The results reveal that the doping effect is heavily dependent on the doping density and a maximal catalytic activity could only be achieved with an optimal doping level. The presence of a macro-pore structure in the trimodal-porous network enhances the mass transport, enabling the full utilization of large surface areas created by micro- and meso-pores. The resultant electrocatalyst possesses high ORR catalytic activity with excellent durability and high resistance to the inhibition effect of fuel molecules. The findings of this work would be valuable for design and fabrication of high performance carbon-based electrocatalysts.