Template Synthesis of Metal Nanowires Containing Monolayer Molecular Junctions

• Published in: Journal of the American Chemical Society Vol. 124; no. 15; pp. 4020 - 4026
• Main Authors: Mbindyo, Jeremiah K. N, Mallouk, Thomas E, Mattzela, James B, Kratochvilova, Irena, Razavi, Baharak, Jackson, Thomas N, Mayer, Theresa S
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 17.04.2002
• Subjects: Chemistry; Exact sciences and technology; General and physical chemistry; Solid-liquid interface; Surface physical chemistry; Interface structure; Monolayer; Atomic force microscopy; Scanning electron microscopy; Gold; Metallic thin films; Liquid solid interface; Transmission electron microscopy; Voltage current curve; Transition metal; Experimental study; Electrical characteristic
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja016696t

Metal nanowires containing in-wire monolayer junctions of 16-mercaptohexanoic acid were made by replication of the pores of 70 nm diameter polycarbonate track etch membranes. Au was electrochemically deposited halfway through the 6 μm long pores and a self-assembled monolayer (SAM) of 16-mercaptohexadecanoic acid was adsorbed on top. A thin layer of Au was then electrolessly grown to form a metal cap separated from the bottom part of the wire by the SAM. Electron micrographs showed that the bottom and top metal segments were separated by an approximately 2 nm thick organic monolayer. Current−voltage measurements of individual nanowires confirmed that the organic monolayer could be contacted electrically on the top and bottom by the metal nanowire segments without introducing electrical short circuits that penetrate the monolayer. The values of the electrical properties for zero-bias resistance, current density, and breakdown field strength were within the ranges expected for a well-ordered alkanethiol SAM of this thickness.