Inverse effects of supporting electrolytes on the electrocatalytic nitrate reduction activities in a Pt|Nafion|Pt–Cu-type reactor assembly

摘要

In this article, the effects of Cl ~(?) and SO _(4) ~(2?) ions on the electrocatalytic nitrate reduction activities in a sandwich-type reactor assembly are illustrated. It was noticed that a Pt|Nafion|Pt–Cu assembly offers its best efficiency in the absence of any supporting electrolytes. The Pt–Cu thin layers adsorb chloride and sulphate ions firmly, and this adsorption blocks the H ~(+) reducing sites at the cathode end of the catalytic assembly, leading to a decrease in catalytic efficiency. In the presence of chloride and sulphate ions, the reduction reactions of NO _(3) ~(?) and NO _(2) ~(?) , respectively, are relatively favoured.