CHARACTERIZATION OF EXTREMELY LOW DEFECT DENSITY HEXADECANETHIOL MONOLAYERS ON HG SURFACES

被引:86
作者
DEMOZ, A [1 ]
HARRISON, DJ [1 ]
机构
[1] UNIV ALBERTA,DEPT CHEM,EDMONTON T6G 2G2,ALBERTA,CANADA
关键词
D O I
10.1021/la00028a028
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Hexadecanethiol (HDT) forms self-assembled monolayers on static Hg drop electrode (SMDE) surfaces. Films are formed in less than 1 min and are extremely impermeable, indicating the absence of defects. The onset of Hg oxidation at about 0.4 V vs SCE on a bare SMDE in 0.1 M NaF is shifted anodically by 1 V on an HDT-coated SMDE. The current for Ru(NH3)63+, methyviologen, benzoquinone, and Fe(CN)63-reduction at an HDT-coated SMDE is <0.005% of that at a bare electrode, and is principally due to capacitive effects. The reduction in differential capacitance upon HDT coating is consistent with the formation of a monolayer film 20 angstrom thick. An upper limit estimate of the apparent electron transfer rate constant for Ru(NH3)63+ at a coated electrode is 3 x 10(-13) cm/s, giving an estimate of the tunneling parameter of 1.5 angstrom-1 and a barrier to tunneling of 2.1 eV. The Pb2+ aquo ion is able to permeate the HDT film, giving currents only 25-fold lower than those at a bare SMDE on the first cycle.
引用
收藏
页码:1046 / 1050
页数:5
相关论文
共 42 条
[1]   CHARGE-TRANSFER AT PARTIALLY BLOCKED SURFACES - A MODEL FOR THE CASE OF MICROSCOPIC ACTIVE AND INACTIVE SITES [J].
AMATORE, C ;
SAVEANT, JM ;
TESSIER, D .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1983, 147 (1-2) :39-51
[2]   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
[3]  
Bard AJ., 1980, ELECTROCHEMICAL METH, P91
[4]   SCANNING TUNNELING MICROSCOPY OBSERVATIONS ON THE RECONSTRUCTED AU(111) SURFACE - ATOMIC-STRUCTURE, LONG-RANGE SUPERSTRUCTURE, ROTATIONAL DOMAINS, AND SURFACE-DEFECTS [J].
BARTH, JV ;
BRUNE, H ;
ERTL, G ;
BEHM, RJ .
PHYSICAL REVIEW B, 1990, 42 (15) :9307-9318
[5]   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
[6]   WATER-STRUCTURE AT INTERFACES - THE PRESENT SITUATION [J].
BOCKRIS, JO ;
JENG, KT .
ADVANCES IN COLLOID AND INTERFACE SCIENCE, 1990, 33 (01) :1-54
[7]  
BOCKRIS JO, 1970, MODERN ELECTROCHEMIS, V2, P725
[8]   SURFACE-STRUCTURE AND THERMAL MOTION OF NORMAL-ALKANE THIOLS SELF-ASSEMBLED ON AU(111) STUDIED BY LOW-ENERGY HELIUM DIFFRACTION [J].
CAMILLONE, N ;
CHIDSEY, CED ;
LIU, GY ;
PUTVINSKI, TM ;
SCOLES, G .
JOURNAL OF CHEMICAL PHYSICS, 1991, 94 (12) :8493-8502
[9]  
CHAMBERS JQ, 1973, ENCY ELECTROCHEMISTR, V12, P329
[10]   CHEMICAL FUNCTIONALITY IN SELF-ASSEMBLED MONOLAYERS - STRUCTURAL AND ELECTROCHEMICAL PROPERTIES [J].
CHIDSEY, CED ;
LOIACONO, DN .
LANGMUIR, 1990, 6 (03) :682-691