Electroreduction of N O_x^z species in alkaline medium on Pt nanoparticles

The electroreduction of nitrogen species in alkaline medium was performed on platinum nanoparticles (1-2 nm) with metal loadings of 5 and 10 wt% Pt, synthesized by the chemical carbonyl route. The electrochemically active surface analysis evidences that the real surface area is concomitant to the Pt-loading in the support. The electrochemical analysis put in evidence that nitrite ions were reduced from -0.6 to -0.78 V and the charge transfer step is attributed to the NO₂^-/NO redox couple. The Tafel slope analysis confirms that from E_p to -0.78 V the reduction of NO occurs via an ECE mechanism. An analysis of Nicholson-Shain schemes and NO-saturated in solution verified these results.