Synthesis of nitrogen-doped carbon catalyst from hydrothermally carbonized wood chips for oxygen reduction

An efficient carbon material was prepared using hydrothermal carbonization of birch-wood chips in the water under elevated pressure, subsequent chemical activation, and doping with nitrogen. The obtained catalyst had a large specific surface area of 2431 m2 g−1 and a high nitrogen content of 4.60 at.%. Most of the nitrogen was in the pyridinic-N (57.61 at.%) form. The synthesized material exhibits excellent electro-catalytic activity for the oxygen reduction reaction with an onset potential of 0.9 V versus the reversible hydrogen electrode, showing the 4e− electrons transfer path in 0.1 M KOH solution.