S, N co-doped rod-like porous carbon derived from S, N organic ligand assembled Ni-MOF as an efficient electrocatalyst for oxygen reduction reaction

Highlights: • A nitrogen and sulfur dual-doped one-dimensional carbon rod catalyst was successfully prepared by pyrolyzing a Ni based MOF. • Graphene-like layers with abundant of mesopores are uniformly and compactly distributed on the surface of Ni-NSPC-6. • A negative shift of only 29.9 mV exists in the electrochemical half-wave potential between Ni-NSPC-6 and Pt/C. • The Ni-NSPC-6 exhibits an excellent ORR durability and a quasi-four-electron oxygen reduction pathway. -- Abstract: Efficient catalyst for the oxygen reduction reaction (ORR) is of significance in the development of fuel cell and metal-air battery technologies. Heteroatom doped carbon materials have been considered as one of most promising alternatives to Pt-based catalysts. In this work, we exploit a nitrogen and sulfur dual-doped one-dimensional carbon rod catalyst with porous graphene-like layers on the surface derived from a Ni based metal-organic framework (MOF). The Ni-NSPC-6 catalyst with uniform distribution of N and S atoms in the carbon skeleton possesses a porous structure and a considerable specific surface area. Benefited from the special one-dimensional morphology, the convenient channel provided by the porous structure, the synergistic effect from the homogeneous co-doping of N and S, and the existence of proper amount of Ni₃S₂, the Ni-NSPC-6 affords a remarkable electrocatalytic performance toward ORR, including positive onset and half-wave potentials, a high catalytic current density, a low Tafel slope for oxygen reduction reaction and a remarkable ORR durability. The controllable synthesis of MOF derived S, N co-doped carbon materials with porous nanostructure will offer prospects in developing high performance electrocatalysts.