Hydrodynamic voltammetric studies of the oxygen reduction at gold nanoparticles-electrodeposited gold electrodes

✍ Scribed by Mohamed S El-Deab; Takeo Ohsaka

• Book ID: 108317875
• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 253 KB
• Volume: 47
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/s0013-4686(02)00487-5

✦ Synopsis

The electrocatalytic reduction of oxygen at Au nanoparticles-electrodeposited Au electrodes has been studied using rotating disk electrode (RDE) voltammetry in 0.5 M H 2 SO 4 . Upon analyzing and comparison of the limiting currents data obtained at various rotation speeds of this RDE with those obtained at the bulk Au electrode, an effective value of the number of electrons, n , involved in the electrochemical reduction of O 2 was estimated to be ca. 4 for the former electrode and ca. 3 for the bulk Au electrode at the same potential of (/350 mV versus Ag/AgCl/KCl(sat.). This indicates the higher possibility of further reduction and decomposition of H 2 O 2 at Au nanoparticles-electrodeposited Au electrode in this acidic medium. The reductive desorption of the self-assembled monolayer of cysteine, which was formed on the Au nanoparticles-electrodeposited Au electrode, was used to monitor the change of the specific activity of the bulk Au electrode upon the electrodeposition of the Au nanoparticles.