کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
192891 | 459754 | 2007 | 11 صفحه PDF | دانلود رایگان |
The electrochemical reduction of nitrate and nitrite anions was investigated on Rh-modified pyrolytic graphite electrodes prepared by potentiostatic electrodeposition with the use of a double-pulse technique. Several important parameters (pH, temperature and composition of electrolytic medium, electrolysis potential) were varied. Only ammonia and nitrite ions were detected among NO3− reduction products, while NO2− ions are straightforwardly reduced to ammonia. The experimental data (CV measurements and the results of electrolyses) clearly show that Rh/graphite electrodes are much more efficient for NO2− reduction than for that of NO3− at room temperature which was confirmed by the determination of rate constants of corresponding reactions and the activation energy of NO2− reduction. The influence of carboxylate anions and tetraalkylammonium cations on the electrocatalytic activity of Rh/graphite electrodes was investigated and the inhibiting effect of HCOO− anions on hydrogen evolution reaction and nitrate reduction was demonstrated.
Journal: Electrochimica Acta - Volume 52, Issue 21, 20 June 2007, Pages 6237–6247