Electroreduction of Nitrates, Nitrites, and Gaseous Nitrogen Oxides: A Potential Source of Ammonia in Dinitrogen Reduction Studies

The results presented herein unambiguously demonstrate that neither nanoparticulate carbon-supported gold, nor bismuth powder are active catalysts for the electrocatalytic dinitrogen reduction, but both can efficiently catalyze the electroreduction of NO₂^–, NO₃^–, NO, and NO₂ to ammonia in an aqueous electrolyte solution. Importantly, reduction of gaseous oxidized forms of nitrogen to NH₃ is more facile and occurs at significantly less negative potentials than that of nitrate and nitrite anions.