Dinitrogen reduction on a polypyrrole coated Pt electrode under high-pressure conditions: Electrochemical impedance spectroscopy studies
Yükleniyor...
Tarih
2015
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
The electrochemical impedance spectroscopy (EIS) responses of a polypyrrole (PPy)-coated platinum electrode were investigated during N2 -reduction to ammonia in aqueous medium. Kinetic parameters such as film resistance, pore resistance, and double layer capacitance were analyzed as a function of applied potential and polymer film thickness. The relation between kinetic parameters was discussed by combining electrolysis results. It was found that the optimum film thickness of polypyrrole was 0.73 µm and optimum potential for ammonia synthesis was –0.150 V under 60 bar N2 -pressure. The impedance responses under these conditions presented the lowest pore resistance value of ca. 2 ? cm2 . The electrolyte resistance was also 2 ? cm2 and the film resistance was ca. 5 ? cm2 . Tafel slopes calculated from the Tafel curve and EIS-Tafel diagram gave corresponding results: 0.121 V dec ?1 and 0.128 V dec ?1 , respectively; ?-transfer coefficient of 0.49 and an exchange current density with a value of 3.17 10 ?3 A cm ?2 were characteristic for Had formation in acidic aqueous medium.
Açıklama
Balun Kayan, Didem (Aksaray, Yazar)
Anahtar Kelimeler
Dinitrogen Reduction, Conducting Polypyrrole Coating, High Pressure Reaction, Electrochemical İmpedance Spectroscopy
Kaynak
Turkish Journal of Chemistry
WoS Q Değeri
N/A
Scopus Q Değeri
Q3
Cilt
39
Sayı
3
