Design and synthesis of conductive carbon polyhedrons enriched with Mn-Oxide active-centres for oxygen reduction reaction

The development of efficient, low-cost and stable electrocatalysts as the alternative to platinum for the oxygen reduction reaction (ORR) is of significance for many important electrochemical devices, such as fuel cells and metal-air batteries. Herein we discuss the design and synthesis of a MnxOy/N-C hybrid catalyst that can address both the activity and durability issues caused by the high productivity of peroxide (H2O2) in nitrogen-doped carbon (N-C). The high activity and stability of the MnxOy/N-C-3 catalyst is ascribed to its novel hybrid structure, in which MnxOy is a good catalyst for decomposition of peroxide, while N-C not only catalyses the ORR but also prevents MnxOy agglomeration. RRDE study indicates a typical 4-electron ORR pathway with very low peroxide production (∼1.9%) and considerable stability. In light of the low cost and high earth abundance of Mn, the highly active MnxOy/N-C is a promising candidate to be used as a cathode material in metal-air batteries and alkaline fuel cells.