Contribution of intermolecular interactions to electron transfer through monolayers of alkanethiols containing amide groups

被引:74
作者
Sek, S [1 ]
Palys, B [1 ]
Bilewicz, R [1 ]
机构
[1] Univ Warsaw, Dept Chem, PL-02093 Warsaw, Poland
关键词
D O I
10.1021/jp013896i
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
Organothiol molecules with one or two amide moieties replacing the methylene groups in the alkyl chain were synthesized and self-assembled in mixed monolayers on the gold electrode. Structures of the monolayer films were studied by STM and electrochemical methods. Reflectance infrared spectroscopy confirmed the formation of intermolecular hydrogen bonds between the amide groups. In the case of diamides, the extent of hydrogen bonding in the external and internal planes of the monolayer were compared and both the odd and the even-membered molecules were considered. Impedance spectroscopy and chronoamperometry were employed to measure the electron transfer rate across mixed monolayers containing less than 10% of electroactive ferrocene organothiol with one or two amide groups in the chain. In the present paper, we focus on the amide location effects on kinetics of mediated electron transfer. Our results indicate that the distance between the planes where amide moieties are located and the electrode surface is of crucial importance. Deeply "buried" (i.e., located close to the electrode surface) amide groups were found to be responsible for the significant increase of electronic coupling comparing to simple n-alkanethiol monolayers. The effect of external amides was much less pronounced, This observation was explained as due to the different extent of hydrogen bonding in the internal and external plane of amide groups.
引用
收藏
页码:5907 / 5914
页数:8
相关论文
共 44 条
[1]   ELECTROCHEMISTRY AT OMEGA-HYDROXY THIOL COATED ELECTRODES .3. VOLTAGE INDEPENDENCE OF THE ELECTRON-TUNNELING BARRIER AND MEASUREMENTS OF REDOX KINETICS AT LARGE OVERPOTENTIALS [J].
BECKA, AM ;
MILLER, CJ .
JOURNAL OF PHYSICAL CHEMISTRY, 1992, 96 (06) :2657-2668
[2]   Electron transport through composite monolayers [J].
Bilewicz, R ;
Sek, S ;
Zawisza, I .
RUSSIAN JOURNAL OF ELECTROCHEMISTRY, 2002, 38 (01) :29-38
[3]  
BILEWICZ R, UNPUB
[4]   Electrochemical and electrochemically modulated reflectance AC voltammetry studies of electron transfer kinetics between attached redox centers and a mirror gold electrode [J].
Brevnov, DA ;
Finklea, HO .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 2000, 147 (09) :3461-3466
[5]   Modulation of electronic coupling through self-assembled monolayers via internal chemical modification [J].
Cheng, J ;
SaghiSzabo, G ;
Tossell, JA ;
Miller, CJ .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1996, 118 (03) :680-684
[6]   FREE-ENERGY AND TEMPERATURE-DEPENDENCE OF ELECTRON-TRANSFER AT THE METAL-ELECTROLYTE INTERFACE [J].
CHIDSEY, CED .
SCIENCE, 1991, 251 (4996) :919-922
[7]   The interplay of lateral and tiered interactions in stratified self-organized molecular assemblies [J].
Clegg, RS ;
Reed, SM ;
Smith, RK ;
Barron, BL ;
Rear, JA ;
Hutchison, JE .
LANGMUIR, 1999, 15 (26) :8876-8883
[8]   Self-assembled monolayers stabilized by three-dimensional networks of hydrogen bonds [J].
Clegg, RS ;
Reed, SM ;
Hutchison, JE .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1998, 120 (10) :2486-2487
[9]   Control of monolayer assembly structure by hydrogen bonding rather than by adsorbate-substrate templating [J].
Clegg, RS ;
Hutchison, JE .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1999, 121 (22) :5319-5327
[10]   Hydrogen-bonding, self-assembled monolayers: Ordered molecular films for study of through-peptide electron transfer [J].
Clegg, RS ;
Hutchison, JE .
LANGMUIR, 1996, 12 (22) :5239-5243