Reduction of Dissolved Oxygen at a Copper Rotating Disc Electrode

Authors

  • Gareth Kear University of Queensland
  • Carlos Ponce-de-Leon Albarran University of Southampton
  • Frank C. Walsh University of Southampton

Abstract

Undergraduates from chemical engineering, applied chemistry, and environmental science courses, together with first-year postgraduate research students in electrochemical technology, are provided with an experiment that demonstrates the reduction of dissolved oxygen in aerated seawater at 25°C. Oxygen reduction is examined using linear sweep voltammetry (i.e., the recording of steady-state current vs. electrode potential curves at a constant potential sweep rate). The use of forced convection to a smooth, rotating disc electrode (RDE) of 3.8 mm diameter (area = 0.113 cm2) in laminar flow provides control of the rate of mass transport of dissolved oxygen toward the cathode surface. The use of rotation speeds in the range of 200-9500 revolutions per minutes (angular velocity of 20-1000 rad s-1) allows a linear (Levich) plot of limiting current vs. the square root of rotation speed to be made. From the slope of this plot, the diffusion coefficient of oxygen can be calculated as (1.5 ± 0.2) x 10-5 cm2 s-1 at 25°C.

Author Biographies

Gareth Kear, University of Queensland

Gareth Kear obtained both his bachelor degree with honors in Applied Chemistry (1998) and his PhD in Applied Electrochemistry (2001) at the University of Portsmouth in the United Kingdom. Gareth is currently a Materials Scientist at the Building Research Association (BRANZ) Limited in Wellington, New Zealand. His work directly concerns the continued development of New Zealand's engineering and construction industries through research, consulting and technology transfer.

Carlos Ponce-de-Leon Albarran, University of Southampton

Carlos Ponce de Leon Albarran has a BSc and an MSc in Chemistry from the Autonomous Metropolitan University, Mexico, and a PhD in Electrochemistry/Electrochemical Engineering from the University of Southampton (1995). His research interests include electrochemical techniques, metal ion removal, characterization of novel electrode materials, electrochemical strategies for pollution control, redox flow cells for energy conversion and electrochemical reactor design.

Frank C. Walsh, University of Southampton

Frank Walsh holds the degrees of BSc in Applied Chemistry from Portsmouth Polytechnic (1975), MSc in Materials Protection following periods of study at UMIST/Loughborough University (1976), and a PhD on electrodeposition in rotating cylinder electrode reactors from Loughborough University (1981). He is the author of over 200 papers and three books in the areas of electrochemistry and electrochemical engineering. Currently, he is Professor in Electrochemical Engineering at the University of Southampton and takes a particular interest in the training of students and industrial engineers in the areas of energy conversion and surface engineering.

Downloads

Published

2005-01-01

Issue

Vol. 39 No. 1 (2005): Winter 2005

Section

Manuscripts