title: Temperature effects on CO adsorption/desorption at Pt film electrodes: an electrochemical in situ infrared spectroscopic study.
abstract: The effects of temperature, CO(ad) surface coverage, and electrode potential on the desorption of CO(ad) from Pt film electrodes in 0.5 M H(2)SO(4) have been investigated by electrochemical in situ FTIR spectroscopy under an attenuated-total-reflection configuration (EC-FTIRS). The major findings are: (i) When theta(rel)>or= 0.53 (theta(CO) is the relative CO(ad) coverage), CO(ad) desorption takes place at T > 40 degrees C (as confirmed by the decrease in both of the C-O(L) stretching frequency as well as the CO(ad) stripping charge), and when theta(rel) is below 0.39, no CO(ad) desorption is observed at temperatures up to 70 degrees C; (ii) A slight increase in CO(ad) desorption rate with electrode potential from 0.1 to 0.3 V and fast adsorption/desorption equilibrium in solution saturated with CO are observed; (iii) From the temperature-dependent changes in CO(ad) surface coverage, the activation energies for CO(ad) desorption are determined to be in the range of 104 and 117 kJ mol(-1), which increases with decreasing CO(ad) coverage.
authors.affiliation: Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Geng
authors.forename: Jun
authors.initials: J
authors.lastname: Cai
authors.forename: Sangzi
authors.initials: S
authors.lastname: Liang
authors.forename: Shao Xiong
authors.initials: SX
authors.lastname: Liu
authors.forename: Ming Fang
authors.initials: MF
authors.lastname: Li
authors.forename: Yan-Xia
authors.initials: YX
authors.lastname: Chen