Catalysis Letters, Vol.149, No.2, 486-495, 2019
Killing Two Birds with One Stone: A Highly Active Tubular Carbon Catalyst with Effective N Doping for Oxygen Reduction and Hydrogen Evolution Reactions
The oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) are two of the core reactions that occur in fuel cells and water electrolysis devices. Heteroatom-doped carbon materials are promising metal-free electrocatalysts to improve the conversion efficiency of these devices. To optimize the nanostructures of such carbon-based catalysts, herein, we reported an effective template method to synthesize N doped carbon nanotubes by using polydopamine as a precursor. The use of the ZnO nanowire not only serves as a self-sacrificial template to direct the formation of the nanotube, but also greatly extends the porosity of the carbon nanotube. Moreover, the polydopamine precursor also leads to effective N doping. An optimized sample, NCNT-900, shows high ORR performance comparable with that of Pt/C as well as good HER performance in both alkaline and acid media, making it one of the most effective carbon-based HER catalysts. This strategy offers an opportunity to synthesize catalysts with higher activity by rational design of a carbon precursor with higher N content or multi-heteroatom co-doping. [GRAPHICS] .