Co/N-doped carbon nanotubes-grafted porous carbon sheets architecture as efficient electrocatalyst for oxygen reduction reaction

The development of high performance and low-cost non-precious metal catalysts (NPMCs) for the oxygen reduction reaction (ORR) to replace platinum-based catalysts is significant in facilitating the commercialization of proton exchange membrance fuel cells (PEMFCs). In this work, a low-cost and effective approach is employed for producing Co/N-doped carbon nanotubes/porous carbon sheets (Co/N-CNT/PCS) catalysts by one-pot annealing of Co salt, melamine and polyvinylpyrrolidone (PVP). The prepared catalysts exhibit a N-doped carbon nanotubes-grafted porous carbon sheets structure, in which Co nanoparticles (Co NPs) encapsulated in bamboo-like CNTs. When compared with a commercial platinum carbon (Pt/C) catalyst in an alkaline solution, one such catalyst (Co/N-CNT/PCS800) displays comparable ORR electrocatalytic activity as well as improved long-team stability and methanol tolerance, arising from the combined effect of high specific surface area, large pore volume and the cooperation of pyridinic-N and graphitic-N. Moreover, given the scalability and economy of this synthesis, Co/N-CNT/PCS catalysts produced in this way are likely to emerge as a major contender as an ORR catalysts in PEMFCs.