[Abstract]This article introduces an improved approach to Fowler-Nordheim (FN) plot analysis, based on a new type of intercept correction factor. This factor is more cleanly defined than the factor previously used. General enabling theory is given that applies to any type of FN plot of data that can be fitted using a FN-type equation. Practical use is limited to emission situations where slope correction factors can be reliably predicted. By making a series of well-defined assumptions and approximations, it is shown how the general formulas reduce to provide an improved theory of orthodox FN-plot data analysis. This applies to situations where the circuit current is fully controlled by the emitter characteristics, and tunneling can be treated as taking place through a Schottky-Nordheim (SN) barrier. For orthodox emission, good working formulas make numerical evaluation of the slope correction factor and the new intercept correction factor quick and straightforward. A numerical illustration, using simulated emission data, shows how to use this improved approach to derive values for parameters in the full FN-type equation for the SN barrier. Good self-consistency is demonstrated. The general enabling formulas also pave the way for research aimed at developing analogous data-analysis procedures for non-orthodox emission situations. PACS: 79.70.+q 3

Field electron emission measurements have been made on composite emitters consisting of electrolytically etched tungsten micropoint cathodes overlayed by a 40-200 nm thick layer of epoxy resin. Their emission properties include (a) an initial switch-on effect at threshold fields of approximately 109 V m-1, (b) a subsequent reversible I-V characteristic that gives a linear FN plot at low fields (or approximately=4*108 V m-1, (c) electron spectra whose FWHM and energy shift is strongly field dependent, (d) single-spot emission images. This unusual pattern of behaviour has been interpreted in terms of a hot electron emission mechanism resulting from field penetration in the dielectric overlayer. Consideration is also given to the technological significance of such composite microemitters.

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This paper presents polymer graphite (PG) as a novel material for the scanning tunneling microscopy (STM) probe. Conductive PG is a relatively modern nanocomposite material used for micro-pencil refills containing a polymer-based binding agent and graphite flakes. Its high conductivity and immunity against surface contamination, with a low price, make it seem like a highly suitable material for electrode manufacturing in general. For the tip production, three methods were developed and are further described in the paper. For the production, three commercially available polymer graphite rods were used. Each has been discussed in terms of performance within the tunneling microscope and within other potential applications.

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Synthesized nanocomposite of protonated polyaniline with camphorsulfonic acid (PANI-CSA) hosted in poly(methyl methacrylate) (PMMA) and incorporated with nickel nanoparticles (NiNPs) were coated as thin films on activated fused silica substrates using oxygen-plasma and spin coating techniques. Weight percent ratios of 0, 10, 20, 30, 60, and 90% of NiNPs with respect to PANI-CSA thin films have been studied in order to investigate the optical, structural, and morphological properties of (PANI-CSA-PMMA)/ NiNPs by employing UV-Vis spectrometer, XRD, scanning electron microscopy (SEM), contact angle (CA) goniometry, impedance analyzer, and thermogravimetric analysis. Deduced refractive indices (n) from UV-Vis data were in the range from 1.5 up to 2.2. SEM micrographs show the typical crystalline structure of PANI was vanishing gradually with increasing the NiNPs content. Optical properties such as refractive index (n), extinction coefficient (k), absorption coefficient (α) as well as the band-gap energies (E g ) were mathematically deduced throughout the experimental transmittance and absorbance UV-Vis spectra. Calculated refractive indices (n) were in the range from 1.5 up to 2.2. Optical band-gap energies decrease in a monoexponential decay for samples up to 60% NiNPs/PANI-CSA, samples with 90% concentration had substantial drop in its value due to the NiNPs percolations. The incorporation with NiNPs leads to the development of a new morphological states (sheet-like heterostructure) which start to be obvious at 30%, at this concentration the CA was maxima (54 ), at this concentration and the crystallite size are maximum and the CA was maximum (highest hydrophobicity).

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