Record Details

The discharge and recovery of the vanadium pentoxide electrode

ScholarsArchive at Oregon State University

Field Value
Title The discharge and recovery of the vanadium pentoxide electrode
Names Watson, Naola VanOrden (creator)
Scott, Allen B. (advisor)
Date Issued 1963-08-06 (iso8601)
Note Graduation date: 1964
Abstract Vanadium pentoxide electrodes were prepared by melting
the powdered oxide around a platinum foil in a pyrex tube. The
electrode was discharged, and the discharge product was studied,
but not identified, by means of chemical and x-ray diffraction analysis.
A study was made of the relationship between the electrode
potential and the pH of the electrolyte solution. It was found that
the number of electrons per hydrogen ion in the discharge reaction
was unity at a pH between two and five.
The electrode potential during discharge was plotted against
the time of discharge and the resulting curves were compared with
curves calculated upon a theory based upon diffusion of the reduction
product into the solid electrode. It was found that the diffusion
equation predicted the shape of the experimental curves.
The diffusion coefficient for the discharge product was
calculated from experimental discharge curves and the equations
for diffusion. A diffusion coefficient of 3 x 10⁻¹⁸ cm² per
sec was obtained.
A mechanism for the discharge and recovery of the vanadium
pentoxide electrode is proposed. It is suggested that the discharge
consists of the reduction of the vanadium pentoxide to a
lower oxy-hydroxide accompanied by an effective diffusion of the
oxy-hydroxide by the migration of protons and electrons into the
body of the electrode. The electrode potential is dependent upon
the composition of the solid solution formed between the pentoxide
and the oxy-hydroxide on the surface of the electrode. The recovery,
after the discharge current is removed, consists of the
further diffusion of the oxy-hydroxide away from the surface and
the resulting increase in the activity of the pentoxide on the surface,
until the composition is uniform throughout the electrode.
Genre Thesis/Dissertation
Topic Electrodes
Identifier http://hdl.handle.net/1957/49037

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