Jinyoung Chun1, Sang K. Jeon2, and Jang H. Chun*,3
1Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, Kyungbuk 790-784,
Republic of Korea
2International Cooperation Division, Korea Institute of Lighting Technology, Bucheon, Kyunggi 420-806, Republic of Korea
3Department of Electronic Engineering, Kwangwoon University, Seoul 139-701, Republic of Korea
At Pt(111), Pt(100), Pt, and Rh interfaces, the Frumkin adsorption isotherm of underpotentially
deposited hydrogen (UPD H) and related electrode kinetic data are determined using
the standard Gibbs energy of adsorption. The Temkin adsorption isotherm of UPD H correlating
with the Frumkin adsorption isotherm of UPD H is readily determined using the correlation
constants between the Temkin and Frumkin or Langmuir adsorption isotherms. At the Pt(111),
Pt(100), Pt, and Rh interfaces, the lateral repulsive interaction between the UPD H species is
interpreted using the interaction parameter for the Frumkin adsorption isotherm. The lateral
repulsive interaction between the UPD H species at the Pt(111), Pt(100), Pt, and Rh interfaces
is significantly different from the lateral attractive interaction between the overpotentially deposited
hydrogen (OPD H) species at Pt, Ir, and Pt-Ir alloy interfaces.
Keyword : Underpotentially and overpotentially deposited hydrogen; Frumkin, Langmuir, and
Temkin adsorption isotherms; Pt group metal electrodes; Standard Gibbs energy of adsorption; Correlation
constants