TY - JOUR
T1 - Understanding the electro-catalytic oxidation mechanism of urea on nickel electrodes in alkaline medium
AU - Vedharathinam, Vedasri
AU - Botte, Gerardine G.
N1 - Funding Information:
The authors would like to thank the financial support of the Center for Electrochemical Engineering Research at Ohio University , and the Department of Defense through the U.S. Army Construction Engineering Research Laboratory ( W9132T-09-1-0001 ). The content of the information does not reflect the position or the policy of the U.S. government. The authors also thank Dr. Madhivanan Muthuvel for his helpful discussion during the project.
PY - 2012/10/30
Y1 - 2012/10/30
N2 - In this paper, the electrocatalytic behavior of urea oxidation on a nickel electrode in alkaline medium was investigated using various electrochemical techniques: cyclic voltammetry (CV), linear sweep voltammetry (LSV), and rotating disc electrode voltammetry (RDE). Possible mechanisms have been proposed on the basis of the cyclic voltammetry data. The urea oxidation current shows a strong dependence on the concentration of urea and potassium hydroxide that enables the experimental determination, by Tafel studies, of the kinetic reaction orders for the oxidation of urea. The Tafel studies show reaction orders of 0.3 and 2, with respect to urea and OH - concentrations, respectively. The diffusion coefficient of urea was found to be 0.85 × 10 -5 cm 2 s -1. The presence of a mixed-controlled process (diffusion and kinetics) was confirmed for the oxidation of urea.
AB - In this paper, the electrocatalytic behavior of urea oxidation on a nickel electrode in alkaline medium was investigated using various electrochemical techniques: cyclic voltammetry (CV), linear sweep voltammetry (LSV), and rotating disc electrode voltammetry (RDE). Possible mechanisms have been proposed on the basis of the cyclic voltammetry data. The urea oxidation current shows a strong dependence on the concentration of urea and potassium hydroxide that enables the experimental determination, by Tafel studies, of the kinetic reaction orders for the oxidation of urea. The Tafel studies show reaction orders of 0.3 and 2, with respect to urea and OH - concentrations, respectively. The diffusion coefficient of urea was found to be 0.85 × 10 -5 cm 2 s -1. The presence of a mixed-controlled process (diffusion and kinetics) was confirmed for the oxidation of urea.
KW - Fuel cells
KW - Hydrogen production
KW - Nickel electrocatalyst
KW - Nickel oxyhydroxide
KW - Urea electro-oxidation
UR - http://www.scopus.com/inward/record.url?scp=84865800861&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2012.07.007
DO - 10.1016/j.electacta.2012.07.007
M3 - Article
AN - SCOPUS:84865800861
SN - 0013-4686
VL - 81
SP - 292
EP - 300
JO - Electrochimica Acta
JF - Electrochimica Acta
ER -