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Carbon nanotube (CNT) devices have been constructed by a post-synthesis alignment, due to difficulties to form a CNT directly on a substrate, whereas CNTs have been found to grow by irradiating an electron beam onto polyyne-containing carbon. This technique is a candidate to construct a CNT device without a metal catalyst by highly geometrically resolvable electron beam lithography. Two types of polyyne-containing carbon (well-aligned and amorphous) are observed and compared by a transmission electron microscope (TEM), providing insights on the formation mechanism and requirements for the precursor. The results suggest that a substantially aligned and not-condensed morphology is essential to form CNTs.

Polyyne-containing carbon has been shown to be converted to carbon nanotubes (CNTs) and carbon onions by irradiating an electron beam. The carbon, which is prepared by a reduction of poly(tetrafluoroethylene) (PTFE), is unstable, reactive, and it is used as a precursor to form carbon nanostructrues. A precise transmission-electron-microscope (TEM) observation reveals that some nanostructures, fibrous and spherical, are already formed in the carbon before the irradiation. The nanostructures are assumed to be formed during the reduction of PTFE. The spherical carbon is well graphitized, whereas the fibrous is not. The reduction is carried out at 0 °C, which is not enough for the fibrous carbon to be well graphitized. The findings suggest a possibility to form a CNT without an electron beam via a reactive polyyne precursor, and are expected to lead an as-designed CNT synthesis.

Scanning force microscopy (SFM) was used to study the surface structure of CF 3 CF 2 (CH 2 ) 6 SH (7,7,8,8,8-pentafluorooctanethiol, PFOT) monolayers self-assembled from a 1 mM trichloroethene (TCE) solution on Au(111). We observed many depressions with several to 20 nm diameters and 0.24 nm depth. In addition, especially around the step edges of Au, mounds 0.3-0.8 nm in height and with lower friction and higher stiffness than those of other regions were observed. These properties would result from the difference in the molecular orientation between on the mounds and on the flat parts. The molecular arrangement with the (√3 x √3) R30° structure was observed on the terraces of Au(111). By comparing the film thickness and the molecular length, the tilt angle of the molecular chain was found to be 56-76° with respect to the surface normal. This large tilt angle allows the PFOT SAMs with the relatively large CF 3 CF 2 - end group to pack closely on the (√3 X √3) R30° structure.

The techniques of scanning force microscopy have been successfully used to investigate phase-separated polymer surfaces on a nanometer scale and been proved to be of great advantage in surface characterization studies of polymers. We observed two kinds of phase-separated surfaces of polystyrene (PS)-polyethylene oxide (PEO) blend film and injection molded crystalline engineering polymer (acetal resin)-elastomer blend plate. In the local mechanical property measurement of the PS-PEO samples, PEO domains were found to be softer and show higher friction force than PS domains with the lateral resolution of less than 100 nm. The results agree qualitatively with those of the bulk. In the local friction measurement of the acetal resin-elastomer blend plate, the surface showed stripe structures 100–300 nm wide: the lower friction region corresponds to acetal resin and the higher one to elastomer. However, in the local elasticity measurement, the difference between the two could not be detected presumably due to the subsurface effect.

Local elasticity was measured on polymers by modifying atomic force microscopy (AFM) in which the sample height was modulated and the response of the cantilever was detected. In a case of polystyrene (PS) on mica, there existed many circular holes in the film that were stiffer than the rest parts. The holes were identified as the substrate mica surface and the rest as PS films. In the case of a polyethyleneoxide surface on mica, a crystalline nature was observed. In addition, the surface was modified by scanning an AFM tip at large forces of 20 nN. The scanned area exhibited an increase in elasticity as well as formation of a striped structure.

We observed molecular resolution images of dibutylamino-triazine-dithiol films on Au(111) with scanning tunneling microscopy. In contrast to the more extensively studied alkanethiols which have only one binding site, the triazine-dithiol has two possible binding sites. The periodic structure of bright spots with different shapes and contrast aligned along the 〈112〉 directions with a spacing of 0.75 nm and 1 nm were imaged. The domain size of the film is 15 nm at most, which is considerably smaller than that of alkanethiol films. The structural stability upon annealing indicates a stronger binding energy of the triazine-dithiol as compared with the alkanethiol. We propose models of the molecular arrangement assuming that the two sulfur atoms of the molecule bind to the substrate.