ABSTRACT
Synthesis and processing techniques have now been established for obtaining high quality monodisperse nanocrystals of various metallic and semiconducting materials, fullerenes of distinct properties, single- and multi-wall carbon nanotubes, polymeric dendrimers with tailored functionalities, as well as other nanophase constructs. The next key step towards novel applications of nanostructured materials concerns their positioning, arrangement, and connection into functional networks without mutual aggregation. In this review, we highlight the recent progress of using anthracene- and pyrene-based self-assembling molecules with tunable energetic (pi-pi interactions, hydrogen bonding, dipole-dipole interactions) and variable geometries to create stable, highly ordered, and rigid self-assembled monolayer (SAM) templates with adjustable superlattices on crystalline substrates. Based on aromatic SAM templates, stable and highly ordered self-assembled structures of optoelectronically active C60 have been obtained and shown to exhibit desirable electrical and optoelectronic properties, such as nonlinear transporting effect for molecular electronics and efficient photocurrent generation for mimicking photosynthesis in nature. By using genetically engineered polypeptides with surface recognition for specific inorganics, selective integration of nanoparticles onto aromatic SAM templates have also been realized. Through a combination of spatially confined surface chemical reaction and microcontact printing, sub-micron arrays of peptide-organic hybrid conjugates were successfully generated to serve as templates to achieve the patterned assembly of nanoparticles.
Subject(s)
Nanostructures/chemistry , Nanotechnology/methods , Chemistry, Organic/methods , Electronics , Fullerenes/chemistry , Genetic Engineering/methods , Hydrogen Bonding , Light , Metal Nanoparticles/chemistry , Nanotubes, Carbon/chemistry , Photochemistry/methods , Photosynthesis , Polymers , Protein Engineering/methods , Surface PropertiesABSTRACT
Hybrid wires composed of metal and conducting polymer (polypyrrole, Ppy) were electrochemically synthesized using a template synthesis method. We showed that the dimensions of the hybrid wires can be tailored by controlling the time of electrolysis. The electrical properties of Ppy having different lengths were measured using a scanning probe microscope (SPM) tip as an electrode without aligning the hybrid wires on a substrate. Especially, temperature-dependent characteristics of the I-V curve were determined. As we expected, the shorter the Ppy wire is, the better the current response produced. The activation energy of each Ppy wire is determined. It is confirmed that the electrical properties of a single wire of Ppy can be measured by SPM.
