Hydrogen evolution at nickel sulphide cathodes in alkaline medium

✍ Scribed by H. Vandenborre; Ph. Vermeiren; R. Leysen

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 298 KB
• Volume: 29
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(84)87065-6

✦ Synopsis

Ahstraet Hydrogen overpotentials at nickel sulphide cathodes have been measured in 1 N NaOH . The nickel sulphide catalysts have been examined for their structure and composition using scanning electron microscopy (SEM) and microprobe analyses . Nickel sulphide electrodes exhibit a transient behaviour during cathodic polarization . A significant increase in performance could be noticed accompanied with a clear change in the mechanism of the evolution reaction. Voltammetric measurements show a first anodic peak around -0.95 V and a second broad peak around -0.65 V . On the basis of galvanostatic potential curves, both anodic peaks have been attributed to oxidation reactions involving hydrogen ; a strongly bonded hydrogen and a dissolved or weakly absorbed hydrogen . It is the formation of the strongly absorbed hydrogen structure which is believed to be the main cause of the observed Iransient behaviour of the nickel sulphide electrodes.