TY - JOUR
T1 - Temperature-dependent kinetic studies of the chlorine evolution reaction over RuO2(110) model electrodes
AU - Sohrabnejad-Eskan, I.
AU - Goryachev, A.
AU - Exner, K.S.
AU - Kibler, L.A.
AU - Hensen, E.J.M.
AU - Hofmann, J.P.
AU - Over, H.
PY - 2017/4/7
Y1 - 2017/4/7
N2 - Ultrathin single-crystalline RuO
2(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
2(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.
AB - Ultrathin single-crystalline RuO
2(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
2(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.
KW - RuO
KW - apparent free activation energy
KW - chlor-alkali electrolysis
KW - chlorine evolution reaction (CER)
KW - oxygen evolution reaction (OER)
KW - selectivity
UR - http://www.scopus.com/inward/record.url?scp=85019716711&partnerID=8YFLogxK
U2 - 10.1021/acscatal.6b03415
DO - 10.1021/acscatal.6b03415
M3 - Article
VL - 7
SP - 2403
EP - 2411
JO - ACS Catalysis
JF - ACS Catalysis
SN - 2155-5435
IS - 4
ER -