Secondary electron (SE) images of the surface of a thin carbon microgrid (CM) firmly covering a copper plate substrate were investigated using a deceleration optics system SEM. The CM was prepared by carbonization of a formvar microgrid used for the transmission electron microscope, 40 nm in thickness, at 700 °C in a N₂ atmosphere, placed on a smooth flat copper plate substrate. The CM is regarded to be composed of a low conductivity material. The estimated thickness was 40 nm. Observation was conducted with the electron probe accelerated at voltages in the range 0.1-30.0 kV. Characteristic SE images of the CM-covered copper plate substrate as a function of accelerating voltage V₀, i.e. probe electron energy E₀, were obtained. The clearest images of the CM surface were observed with E₀ in the range 0.1-1.0 keV. The variation of the SE image versus E₀ was interpreted with the aid of a Monte Carlo electron trajectory simulation for the CM-covered copper plate substrate.

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1-aminpyrene was reacted with graphite oxide (GO) in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloric salt as a catalyst. As the reaction time and the concentration of 1-aminopyrene increased, the amount of attached 1-aminopyrene increased and reached 6.9 mmol/100 g GO. At the same time, the interlayer spacing of the GO increased to 1.26 nm. Based on various spectroscopic measurements, it has been proved that two reactions mainly occurred: (a) an acid-base reaction between hydroxyl groups on the basal plane of the GO and protonated amine, and (b) the formation of amide bonding between 1-aminopyrene and carboxylic groups on the edge of GO. In the course of these reactions, partial reduction of GO layers also occurred. The 1-aminopyrene molecules in (a) are almost completely removed and those in (b) are partially removed by treating with HCl, which was accompanied by further reduction of the GO.

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