Hydrogen evolution on platinum in the presence of lead, cadmium and thallium adatoms
Abstract
Hydrogen evolution on rotating platinum electrode has been measured in the presence of Pb, Tl and Cd adatoms. At low coverages of these adatoms (θM < 0.5) the mechanism of H2 evolution is the same as that for Pt, giving rise to the Tafel slope of 30 mV with recombination of H adatoms as a rate controlling step. However, H2 evolution decreases with θM to the fourth power, due to a simple blocking of Pt surface and a decrease of number of pairs of Pt atoms necessary for a recombination reaction. At higher coverages of foreign metal adatoms (θM ≥ 0.5), when the activation energy for the recombination of H adatoms becomes too high, the ion-plus atom reaction begins to control the rate of reaction. The Tafel slope acquires a value of 120 mV. Now, a decrease of H2 evolution has been found proportional to the coverage of metal adatoms. A quantitative analysis based on above model agrees very well with the experiment. Some information on underpotential deposition of above metal on Pt has al...so been obtained. © 1979.
Source:
Electrochimica Acta, 1979, 24, 5, 569-576Publisher:
- Pergamon Press
Funding / projects:
- Council of Yugoslav Academies of Sciences
- National Academy of Science.
- Research Fund of Serbia
- Serbian Academy of Sciences
Collections
Institution/Community
IHTMTY - JOUR AU - Adžić, Radoslav R. AU - Spasojević, M. D. AU - Despić, Aleksandar R. PY - 1979 UR - https://cer.ihtm.bg.ac.rs/handle/123456789/2751 AB - Hydrogen evolution on rotating platinum electrode has been measured in the presence of Pb, Tl and Cd adatoms. At low coverages of these adatoms (θM < 0.5) the mechanism of H2 evolution is the same as that for Pt, giving rise to the Tafel slope of 30 mV with recombination of H adatoms as a rate controlling step. However, H2 evolution decreases with θM to the fourth power, due to a simple blocking of Pt surface and a decrease of number of pairs of Pt atoms necessary for a recombination reaction. At higher coverages of foreign metal adatoms (θM ≥ 0.5), when the activation energy for the recombination of H adatoms becomes too high, the ion-plus atom reaction begins to control the rate of reaction. The Tafel slope acquires a value of 120 mV. Now, a decrease of H2 evolution has been found proportional to the coverage of metal adatoms. A quantitative analysis based on above model agrees very well with the experiment. Some information on underpotential deposition of above metal on Pt has also been obtained. © 1979. PB - Pergamon Press T2 - Electrochimica Acta T2 - Electrochimica Acta T1 - Hydrogen evolution on platinum in the presence of lead, cadmium and thallium adatoms VL - 24 IS - 5 SP - 569 EP - 576 DO - 10.1016/0013-4686(79)85034-3 ER -
@article{ author = "Adžić, Radoslav R. and Spasojević, M. D. and Despić, Aleksandar R.", year = "1979", abstract = "Hydrogen evolution on rotating platinum electrode has been measured in the presence of Pb, Tl and Cd adatoms. At low coverages of these adatoms (θM < 0.5) the mechanism of H2 evolution is the same as that for Pt, giving rise to the Tafel slope of 30 mV with recombination of H adatoms as a rate controlling step. However, H2 evolution decreases with θM to the fourth power, due to a simple blocking of Pt surface and a decrease of number of pairs of Pt atoms necessary for a recombination reaction. At higher coverages of foreign metal adatoms (θM ≥ 0.5), when the activation energy for the recombination of H adatoms becomes too high, the ion-plus atom reaction begins to control the rate of reaction. The Tafel slope acquires a value of 120 mV. Now, a decrease of H2 evolution has been found proportional to the coverage of metal adatoms. A quantitative analysis based on above model agrees very well with the experiment. Some information on underpotential deposition of above metal on Pt has also been obtained. © 1979.", publisher = "Pergamon Press", journal = "Electrochimica Acta, Electrochimica Acta", title = "Hydrogen evolution on platinum in the presence of lead, cadmium and thallium adatoms", volume = "24", number = "5", pages = "569-576", doi = "10.1016/0013-4686(79)85034-3" }
Adžić, R. R., Spasojević, M. D.,& Despić, A. R.. (1979). Hydrogen evolution on platinum in the presence of lead, cadmium and thallium adatoms. in Electrochimica Acta Pergamon Press., 24(5), 569-576. https://doi.org/10.1016/0013-4686(79)85034-3
Adžić RR, Spasojević MD, Despić AR. Hydrogen evolution on platinum in the presence of lead, cadmium and thallium adatoms. in Electrochimica Acta. 1979;24(5):569-576. doi:10.1016/0013-4686(79)85034-3 .
Adžić, Radoslav R., Spasojević, M. D., Despić, Aleksandar R., "Hydrogen evolution on platinum in the presence of lead, cadmium and thallium adatoms" in Electrochimica Acta, 24, no. 5 (1979):569-576, https://doi.org/10.1016/0013-4686(79)85034-3 . .