Single electron tunneling and manipulation of nanoparticles on surfaces at room temperature

Department of Chemistry, University of California, 95616, Davis, CA, USA; Department of Chemistry and Biochemistry, University of California, 95064, Santa Cruz, CA, USA
Surface Science (Impact Factor: 1.87). 07/2005; 589(1). DOI: 10.1016/j.susc.2005.05.061

ABSTRACT This article focuses on surfaces containing nanoparticles and self-assembled monolayers (SAMs). These surfaces provide a simple and reliable platform for measurements of single electron tunneling (SET) properties of metal nano-particles at room temperature. This approach of interfacial chemistry allows for the elimination of lateral motion of the individual nanoparticles during electronic property studies. The scanning tunneling microscopy (STM) in ultra-high vacuum is used as an accurate and reproducible probe for imaging and I–V characterization of individual or aggregated Au nanoparticles, revealing a large Coulomb gap (1.0 eV) and fine Coulomb staircases (0.2–0.3 eV) at room tempera-ture. The surrounding decanethiol SAM provides an ideal reference for the imaging and I–V measurements of nano-particles. These measurements provide a quantitative guide for regulating current and voltage, at which individual Au nanoparticles may be detached and manipulated with the STM tip.

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