Nitrogenated-Graphite-Encapsulated Carbon Black as a Metal-Free Electrocatalyst for the Oxygen Evolution Reaction in Acid

No metal needed: A core-shell-like carbon catalyst consisting of a few layers of nitrogen-doped graphite on a carbon black core was prepared by pyrolyzing an ionic liquid (IL) with carbon black (CB) particles. The catalyst has a noticeably improved OER performance of the nanocarbon in acid solution. The resilience of the catalyst in acid solution is due to the greater protection of the nitrogen-containing OER active sites in a graphitic shell. The oxygen evolution reaction (OER) in acid solution is very challenging for metal-free catalysts based only on heteroatom-doped carbon nanomaterials which have thus far shown relatively low catalytic activity and poor stability. Herein, we report a core-shell-like carbon catalyst consisting of a few layers of nitrogen-doped graphite on a carbon black core prepared by pyrolyzing an ionic liquid (IL) with carbon black (CB) particles. The catalyst prepared as such has a noticeably improved OER performance of the nanocarbon in acid solution (1.70 V at a current density of 10 mA cm(-2)) in comparison with the few metal-free OER electrocatalysts reported to date. The experimental results suggest that the resilience of the catalyst in acid solution is due to the greater protection of the nitrogen-containing OER active sites in a graphitic shell.