1 research outputs found
Temperature-Dependent Kinetic Studies of the Chlorine Evolution Reaction over RuO<sub>2</sub>(110) Model Electrodes
Ultrathin
single-crystalline RuO<sub>2</sub>(110) films supported
on Ru(0001) are employed as model electrodes to extract kinetic information
about the industrially important chlorine evolution reaction (CER)
in a 5M concentrated NaCl solution under well-defined electrochemical
conditions and variable temperatures. A combination of chronoamperometry
(CA) and online electrochemical mass spectrometry (OLEMS) experiments
provides insight into the selectivity issue: At pH = 0.9, the CER
dominates over oxygen evolution, whereas at pH = 3.5, oxygen evolution
and other parasitic side reactions contribute mostly to the total
current density. From temperature-dependent CA data for pH = 0.9,
we determine the apparent free activation energy of the CER over RuO<sub>2</sub>(110) to be 0.91 eV, which compares reasonably well with the
theoretical value of 0.79 eV derived from first-principles microkinetics.
The experimentally determined apparent free activation energy of 0.91
eV is considered as a benchmark for assessing future improved theoretical
modeling from first principles