Enhanced chain densities of n-alkanethiolate self-assembled monolayers on gold from aqueous micellar solutions

Langmuir

Volumn 16, Issue 20, 2000, Pages 7562-7565

  Yan, Dong ^a   Saunders, Jeremy A ^a   Jennings, G Kane ^a  

^a VANDERBILT UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

DENSITY (SPECIFIC GRAVITY); DIFFUSION; ELECTROCHEMISTRY; ETHANOL; ETHERS; GOLD; HYDROPHOBICITY; INFRARED SPECTROSCOPY; MICELLES; MOLECULAR DYNAMICS; MOLECULAR STRUCTURE; REDOX REACTIONS;

ALKANETHIOLATE; CHAIN DENSITIES; HEXAETHYLENE GLYCOL MONODODECYL ETHER; HYDROPHOBIC INTERACTIONS; SELF ASSEMBLED MONOLAYERS;

MONOLAYERS;

EID: 0034300103     PISSN: 07437463     EISSN: None     Source Type: Journal    
DOI: 10.1021/la000850s     Document Type: Article

References (30)

1. Ulman, A., Ed. Thin Films; Academic Press: Boston, MA, 1998; Vol. 24.
2. Laibinis, P. E.; Palmer, B. J.; Lee, S.-W.; Jennings, G. K. The Synthesis of Organothiols and their Assembly into Monolayers on Gold. In Thin Films; Ulman, A., Ed.; Academic Press: Boston, MA, 1998; Vol. 24, pp 1-41.
3. Kim, H. I.; Graupe, M. B.; Oloba, O.; Koini, T.; Imaduddin, S.; Lee, T. R.; Perry, S. S. Langmuir 1999, 15, 3179-3185.
4. Laibinis, P. E.; Whitesides, G. M. J. Am. Chem. Soc. 1992, 114, 1990-1995.
5. Prime, K. L.; Whitesides, G. M. J. Am. Chem. Soc. 1993, 115, 10714-10721.
6. Finklea, H. O. Electrochemistry of Organized Monolayers ofThiols and Related Molecules on Electrodes. In Electroanalytical Chemistry; Bard, A. J., Rubinstein, I., Eds.; Marcel Dekker: New York, 1996; Vol. 19, pp 109-335.
7. Diallo, M. S.; Abriola, L. M.; Weber, W. J. Environ. Sci. Technol. 1994, 28, 1829-1837.
8. Israelachvili, J. Intermolecular & Surface Forces, 2nd ed.; Academic Press: San Diego, CA, 1992.
9. Puvvada, S.; Blankschtein, D. J. Chem. Phys. 1990, 92, 3710-3724.
10. Briganti, G.; Puvvada, S.; Blankschtein, D. J. Phys. Chem. 1991, 95, 8989-8995.
11. Miller, C.; Cuendet, P.; Gratzel, M. J. Phys. Chem. 1991, 95, 877-886.
12. Liu, J.; Kaifer, A. E. Isr. J. Chem. 1997, 37, 235-239.
13. Laibinis, P. E.; Whitesides, G. M.; Allara, D. L.; Tao, Y.-T.; Parikh, A. N.; Nuzzo, R. G. J. Am. Chem. Soc. 1991, 113, 7152-7167.
14. On the basis of the positions and intensities of the asymmetric and symmetric methylene modes, spectra of SAMs formed from isooctane were of similar crystallinity but were more canted on average than SAMs formed from ethanol.
15. On the basis of the surface selection rule, the integrated intensity for a given mode is proportional to the square of the component of its dynamic dipole moment along the surface normal. See: Greenler, R. G. J. Chem. Phys. 1966, 44, 310-314.
16. 2 in a KBr matrix.
17. 13 On the basis of a (√3 × √3)R30° overlayer of thiolates on Au(111), we would expect the chains to cant ∼30°. That our measured cant values are less than 30° could be due to our use of a polycrystalline gold surface. While exhibiting a predominant (111) texture, the surface of polycrystalline gold often contains regions of other textures that can foster increased packing density of alkanethiols. For example, alkanethiolate SAMs are less canted on electroless gold that exhibits primarily (111) texture but also significant (200), (220), and (311) textures. See: Hou, Z.; Abbott, N. L.; Stroeve, P. Langmuir 1998, 14, 3287-3297. We emphasize that the cant and twist values reported here are merely estimates based on a single-chain model and should not be taken as exact values. Nevertheless, the difference in cant between the aqueous and ethanolic SAMs is useful to characterize relative differences in overall chain density.
18. Xu, S.; Cruchon-Dupeyrat, S.; Garno, J. C.; Liu, G.-Y.; Jennings, G. K.; Yong, T.-H.; Laibinis, P. E. J. Chem. Phys. 1998, 108, 5002-5012.
19. Dubois, L. H.; Nuzzo, R. G. Annu. Rev. Phys. Chem. 1992, 43, 437-463 and references therein.
20. Sellers, H.; Ulman, A.; Shnidman, Y.; Eilers, J. J. Am. Chem. Soc. 1993, 115, 9389-9401.
21. Schonenberger, C.; Jorritsma, J.; Sondag-Huethorst, J. A. M.; Fokkink, L. G. J. J. Phys. Chem. 1995, 99, 3259-3271.
22. Terrill, R. H.; Tanzer, T. A.; Bohn, P. W. Langmuir 1998, 14, 845-854.
23. Bain, C. D.; Troughton, E. B.; Tao, Y.-T.; Evall, J.; Whitesides, G. M.; Nuzzo, R. G. J. Am. Chem. Soc. 1989, 111, 321-335.
24. Bensebaa, F.; Voicu, R.; Huron, L.; Ellis, T. H. Langmuir 1997, 13, 5335-5340.
25. Stole, S. M.; Porter, M. D. Langmuir 1990, 6, 1199-1202.
26. Hatchett, D. W.; Uibel, R. H.; Stevenson, K. J.; Harris, J. M.; White, H. S. J. Am. Chem. Soc. 1998, 120, 1062-1069.
27. Nuzzo, R. G.; Zegarski, B. R.; Dubois, L. H. J. Am. Chem. Soc. 1987, 109, 733-740.
28. 6(aq) and those formed in ethanol, the increases in overall chain density that we observe are more likely due to SAMs with larger domains of (√3 × √3)R30° structure and fewer defects.
29. Porter, M. D.; Bright, T. B.; Allara, D. L.; Chidsey, C. E. D. J. Am. Chem. Soc. 1987, 109, 3559-3568.
30. Jennings, G. K.; Munro, J. C.; Yong, T.-H.; Laibinis, P. E. Langmuir 1998, 14, 6130-6139.