Nanowire-Templated Synthesis of FeNx-Decorated Carbon Nanotubes as Highly Efficient, Universal-pH, Oxygen Reduction Reaction Catalysts

Graphical Doped to reduce : FeN x -decorated carbon nanotubes are prepared by utilizing ZnO nanowires as a sacrificial template and Fe–polydopamine (Fe–PDA) complex as metal and carbon sources (see figure). The evaporation of Zn at high temperature results in a high surface area of the carbon nanotubes, and the FeN x species contribute greatly to the oxygen reduction reaction activity of the catalyst. It is of increasing importance to develop highly active and economical oxygen reduction reaction (ORR) electrocatalysts, which have great significance for the large-scale implementation of various energy conversion systems, including metal–air batteries and fuel cells. Herein, a novel method to synthesize FeN x -decorated carbon nanotubes as a high-efficiency ORR catalyst, by utilizing ZnO nanowires as a sacrificial template and a Fe–polydopamine complex as metal and carbon sources, is reported. The obtained catalyst shows great potential for replacing Pt/C as the ORR catalyst under various pH conditions, from alkaline to acidic electrolytes. The high conductivity, large surface area of the carbon nanotube, and highly active FeN x species contributed greatly to the high performance of the catalyst. The work presented herein paves a new way for the synthesis of 1D porous nanomaterials for a broad range of energy-related applications.