Nitrogen-doped hollow carbon hemispheres as efficient metal-free electrocatalysts for oxygen reduction reaction in alkaline medium

Honeycomb-like N-doped hollow carbon hemispheres are synthesized by a facile and versatile process, using ionic liquids as the carbon source. The resulting materials show a unique hollow hemisphere morphology, outstanding electrochemical activity, strong immunity towards methanol crossover and stability superior to the commercial Pt/C catalyst in alkaline medium.