Nitrogen-doped carbon nanomaterials as non-metal electrocatalysts for water oxidation

Efficient and low-cost electrocatalysts for the oxygen evolution reaction are essential components of renewable energy technologies, such as solar fuel synthesis and providing a hydrogen source for powering fuel cells. Here we report that the nitrogen-doped carbon materials function as the efficient oxygen evolution electrocatalysts. In alkaline media, the material generated a current density of 10 mA cm−2 at the overpotential of 0.38 V, values that are comparable to those of iridium and cobalt oxide catalysts and are the best among the non-metal oxygen evolution electrocatalyst. The electrochemical and physical studies indicate that the high oxygen evolution activity of the nitrogen/carbon materials is from the pyridinic-nitrogen- or/and quaternary-nitrogen-related active sites. Our findings suggest that the non-metal catalysts will be a potential alternative to the use of transition metal-based oxygen evolution catalysts. Efficient and economical water splitting is desirable for energy conversion, but it is limited by high overpotential and the need for noble metals. Zhao et al. report that nitrogen-doped graphite materials function as a promising electrocatalyst, with efficiency comparable to that of benchmark metal oxides.