Temperature effects on the voltammetry of ferrocene terminated self-assembled monolayers

被引:6
作者
Brett, DJL [1 ]
Williams, R [1 ]
Wilde, CP [1 ]
机构
[1] Univ London Imperial Coll Sci Technol & Med, Dept Chem, Interfacial Sci Grp, London SW7 2AY, England
来源
JOURNAL OF ELECTROANALYTICAL CHEMISTRY | 2002年 / 538卷
关键词
monolayers; organised molecular assembly; ferrocene; temperature; cyclic voltammetry;
D O I
10.1016/S0022-0728(02)01216-0
中图分类号
O65 [分析化学];
学科分类号
070302 ; 081704 ;
摘要
The voltammetry of self-assembled monolayers (SAMs) of 11-mercaptoundecyl-ferrocenecarboxylate (FcCOO(CH2)(11)SH) has been studied as a function of temperature. Such SAMs are, when oxidised, susceptible to loss of ferrocene via nucleophilic attack, but at temperatures only just above room temperature, there is an accelerated loss of ferrocene from the chain termini, an increase in the capacitance of the layer in its reduced state and a positive shift in the E-1/2 value. A comparison between these data and the effects of multiple scans recorded at room temperature suggests that there is a re-orientation, induced at slightly elevated temperatures, which is associated with the ferrocene ester linkage at the chain terminus and which apparently renders ferrocene more susceptible to nucleophilic attack. Accelerated loss of ferrocene with temperature increases the permeability of the layer and hence its capacitance. The positive shift of the E-1/2 value is harder to interpret but may result because the ferrocene is in more intimate contact with the layer and is placed in a more hydrophobic, less polar environment. Other possible influences on the shift of E-1/2 are discussed. This work confirms that electroactive terminal groups can provide information on the micro-environment at the SAM \ electrolyte interface through variations in current and potential. (C) 2002 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:65 / 74
页数:10
相关论文
共 44 条
[1]  
ANGERSTEINKOZLO.H, 1984, COMPR TREAT, V9, P22
[2]  
Aramata A., 1997, MODERN ASPECTS ELECT
[3]   PHASE-TRANSITIONS IN SELF-ASSEMBLED MONOLAYERS DETECTED BY ELECTROCHEMISTRY [J].
BADIA, A ;
BACK, R ;
LENNOX, RB .
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1994, 33 (22) :2332-2335
[4]   FORMATION OF MONOLAYER FILMS BY THE SPONTANEOUS ASSEMBLY OF ORGANIC THIOLS FROM SOLUTION ONTO GOLD [J].
BAIN, CD ;
TROUGHTON, EB ;
TAO, YT ;
EVALL, J ;
WHITESIDES, GM ;
NUZZO, RG .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1989, 111 (01) :321-335
[5]   Thermal treatment of n-alkanethiolate monolayers on gold, as observed by infrared spectroscopy [J].
Bensebaa, F ;
Ellis, TH ;
Badia, A ;
Lennox, RB .
LANGMUIR, 1998, 14 (09) :2361-2367
[6]   Voltammetric studies of ferrocene and the mercury dithiophosphate system at mercury electrodes over a temperature range encompassing the mercury liquid-solid state transition [J].
Bond, AM ;
Colton, R ;
Harvey, J ;
Hutton, RS .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1997, 426 (1-2) :145-155
[7]   COADSORPTION OF FERROCENE-TERMINATED AND UNSUBSTITUTED ALKANETHIOLS ON GOLD - ELECTROACTIVE SELF-ASSEMBLED MONOLAYERS [J].
CHIDSEY, CED ;
BERTOZZI, CR ;
PUTVINSKI, TM ;
MUJSCE, AM .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1990, 112 (11) :4301-4306
[8]   FREE-ENERGY AND TEMPERATURE-DEPENDENCE OF ELECTRON-TRANSFER AT THE METAL-ELECTROLYTE INTERFACE [J].
CHIDSEY, CED .
SCIENCE, 1991, 251 (4996) :919-922
[9]   COMPETITIVE SELF-ASSEMBLY AND ELECTROCHEMISTRY OF SOME FERROCENYL-N-ALKANETHIOL DERIVATIVES ON GOLD [J].
CREAGER, SE ;
ROWE, GK .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1994, 370 (1-2) :203-211
[10]   Solvent and double-layer effects on redox reactions in self-assembled monolayers of ferrocenyl-alkanethiolates on gold [J].
Creager, SE ;
Rowe, GK .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1997, 420 (1-2) :291-299