TY - JOUR
T1 - Do alkanethiols adsorb onto the surfaces of TI-Ba-Ca-Cu-O-based high-temperature superconductors? The critical role of H2O content on the adsorption process
AU - Chen, Kaimin
AU - Xu, Feng
AU - Mirkin, Chad A.
AU - Lo, Rung Kuang
AU - Nanjundaswamy, K. S.
AU - Zhou, Ji Ping
AU - McDevitt, John T.
PY - 1996/5/29
Y1 - 1996/5/29
N2 - The reactivity of Tl1.4Ba2CaCu2O7.0, a high-temperature superconductor (HTSC), toward a redox-active adsorbate molecule with thiol functionality has been investigated as a function of solvent type and H2O content. Previously it had been reported that alkanethiols do not stably chemisorb onto the surface of Tl2Ba2CaCu2O8/Tl2Ba 2Ca2Cu3O10 phases, bringing into question the generality of alkanethiol adsorption onto cuprate-based HTSCs. Herein, we show that under rigorously dry conditions, 11-mercaptounde-canoylferrocene (1) adsorbs cleanly onto the surface of Tl1.4Ba2CaCu2O7.0 to form moderately stable, redox-active monolayer films. The redox activity of 1 was used to estimate adsorbate surface coverage, and it is shown that the addition of H2O to the modifying solutions of 1 adversely affects the monolayer adsorption process. No redox activity associated with 1 could be detected for electrodes soaked in 0.1 M solutions of 1 with 5% H2O in ethanol, which was attributed to the formation of a BaCO3 corrosion layer that prohibited the adsorption of 1 onto the HTSC surface. The importance of sample stoichiometry on the adsorption process also is discussed.
AB - The reactivity of Tl1.4Ba2CaCu2O7.0, a high-temperature superconductor (HTSC), toward a redox-active adsorbate molecule with thiol functionality has been investigated as a function of solvent type and H2O content. Previously it had been reported that alkanethiols do not stably chemisorb onto the surface of Tl2Ba2CaCu2O8/Tl2Ba 2Ca2Cu3O10 phases, bringing into question the generality of alkanethiol adsorption onto cuprate-based HTSCs. Herein, we show that under rigorously dry conditions, 11-mercaptounde-canoylferrocene (1) adsorbs cleanly onto the surface of Tl1.4Ba2CaCu2O7.0 to form moderately stable, redox-active monolayer films. The redox activity of 1 was used to estimate adsorbate surface coverage, and it is shown that the addition of H2O to the modifying solutions of 1 adversely affects the monolayer adsorption process. No redox activity associated with 1 could be detected for electrodes soaked in 0.1 M solutions of 1 with 5% H2O in ethanol, which was attributed to the formation of a BaCO3 corrosion layer that prohibited the adsorption of 1 onto the HTSC surface. The importance of sample stoichiometry on the adsorption process also is discussed.
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M3 - Article
AN - SCOPUS:0012740856
VL - 12
SP - 2622
EP - 2624
JO - Langmuir
JF - Langmuir
SN - 0743-7463
IS - 11
ER -