Self-assembled monolayers composed of aromatic thiols on gold: Structural characterization and thermal stability in solution

被引:84
作者
Garg, N [1 ]
Carrasquillo-Molina, E [1 ]
Lee, TR [1 ]
机构
[1] Univ Houston, Dept Chem, Houston, TX 77204 USA
关键词
D O I
10.1021/la0115278
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Self-assembled monolayers (SAMs) derived from 1,2-bis(mercaptomethyl)-4,5-dialkylbenzene (1), 1-mercaptomethyl-3,4-dialkylbenzene (2),1-mercaptomethyl-4-alkylbenzene (3),1-mercapto-4-alkylbenzene (4), and 4-mercaptomethyl-4'-alkoxybiphenyl (5) were prepared by adsorption from solution onto evaporated gold. The SAMs were characterized by contact angle goniometry, optical ellipsometry, and polarization modulation infrared reflection absorption spectroscopy. Comparison of SAMs generated from 1 and 2 to well-known SAMs generated from normal alkanethiols (6) revealed that the former SAMs are densely packed and highly oriented. The alkyl chains of the SAMs derived from 1 and 2 are, however, less crystalline (i.e., less conformationally ordered) than those derived from 6. The adsorption of compounds 3, 4, and 5 onto gold yielded highly crystalline SAMs. Solution-phase thermal desorption of SAMs 1-6 at temperatures ranging from 60 to 110 degreesC was monitored using ex situ ellipsometry. The desorption profiles of SAMs derived from 1-6 revealed two distinct kinetic regimes: a fast initial desorption followed by a substantially slower desorption. The rates of film desorption in both regimes were observed to increase with increasing temperature. Comparison of the desorption profiles of SAMs 1-6 showed that the structure of the adsorbate strongly influenced the rate of desorption; the differences were more apparent during the advanced stages of desorption. These studies provided a framework for evaluating the structural features and the mechanistic pathways that dictate the thermal stability of SAMs on gold.
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页码:2717 / 2726
页数:10
相关论文
共 60 条
[1]  
ALLARA DL, 1995, CHARACTERIZATION ORG, P57
[2]   Influence of solvent on the interfacial structure of self-assembled alkanethiol monolayers [J].
Anderson, MR ;
Evaniak, MN ;
Zhang, MH .
LANGMUIR, 1996, 12 (10) :2327-2331
[3]   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
[4]   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
[5]   COMPARISON OF ORGANIC MONOLAYERS ON POLYCRYSTALLINE GOLD SPONTANEOUSLY ASSEMBLED FROM SOLUTIONS CONTAINING DIALKYL DISULFIDES OR ALKENETHIOLS [J].
BIEBUYCK, HA ;
BIAN, CD ;
WHITESIDES, GM .
LANGMUIR, 1994, 10 (06) :1825-1831
[6]   AN ANALYSIS OF SOLID PHASE BEHAVIOR OF NORMAL PARAFFINS [J].
BROADHURST, MG .
JOURNAL OF RESEARCH OF THE NATIONAL BUREAU OF STANDARDS SECTION A-PHYSICS AND CHEMISTRY, 1962, 66 (03) :241-+
[7]   POLARIZATION MODULATION FT-IR SPECTROSCOPY OF SURFACES AND ULTRA-THIN FILMS - EXPERIMENTAL PROCEDURE AND QUANTITATIVE-ANALYSIS [J].
BUFFETEAU, T ;
DESBAT, B ;
TURLET, JM .
APPLIED SPECTROSCOPY, 1991, 45 (03) :380-389
[8]   PREDICTING THE STABILITY OF CYCLIC DISULFIDES BY MOLECULAR MODELING - EFFECTIVE CONCENTRATIONS IN THIOL-DISULFIDE INTERCHANGE AND THE DESIGN OF STRONGLY REDUCING DITHIOLS [J].
BURNS, JA ;
WHITESIDES, GM .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1990, 112 (17) :6296-6303
[9]   Fabrication of extended conjugation length polymers within diacetylene monolayers on Au surfaces: Influence of UV exposure time [J].
Cai, M ;
Mowery, MD ;
Menzel, H ;
Evans, CE .
LANGMUIR, 1999, 15 (04) :1215-1222
[10]   X-ray photoelectron spectroscopy sulfur 2p study of organic thiol and disulfide binding interactions with gold surfaces [J].
Castner, DG ;
Hinds, K ;
Grainger, DW .
LANGMUIR, 1996, 12 (21) :5083-5086