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The investigation of the relation of catalyst particles with resultant carbon deposits has been carried out. In this paper, the influences of catalyst particles on the morphology of carbon fibers are studied. Carbon fibers have been synthesized by the decomposition of methanol/ethanol over copper substrate via catalytic combustion technique and chemical vapor deposition method. The structural characteristics of the carbon product were assessed from the scanning electron microscopy. In situ scanning electron microscopy showed that the size and the shape of the catalyst particles can influence the morphology of the resultant carbon fibers.

A simple method is presented for the preparation of silica nano-rods. The silica nano-rods with a diameter of about 200 nm with smooth surface were synthesized by chemical vapor deposition method at 1300square. The as-synthesized samples were characterized by means of scanning electron microscopy, energy dispersive x-ray, and transmission electron microscopy. The results show that synthesized silica nano-rods have a uniform size, well-defined shape, and smooth surface. However, the morphologies and microstructures of silica nano-rods are affected by synthesis conditions, such as the synthesis temperature and the vapor concentration of the SiOx. On the basis of these experimental results, a possible growth mechanism of silica nano-rods in this process is proposed.

In this paper, we report the growth of lead zirconate titanate (PZT) ferroelectric thin films, formed by means of the electrochemical reduction. In our experiment, the electrolyte was prepared by lead nitrate (Pb(NO3)2), zirconium oxide chloride (ZrOCl2-8H2O) and titanium chloride (TiCl3) solution. A graphite plate with 1 cm of width was employed as the anode, and a stainless steel plate was employed as both cathode and substrate. The controlled current that was supplied by a DC power supply passed through the electrolyte to deoxidize PZT precursor films on the surface of the stainless steel at room temperature. The results indicate that the atomic ratio of compositions in the film can be controlled by controlling the molar concentration of electrolytic solution, current density and reaction time. The perovskite PZT thin films can be obtained when the precursor films are heated to a certain temperature for sintering.

Here, a simple and low cost catalytic combustion method was employed for preparation of ribbon-like carbon fibers. A lot of multi-directionally grown ribbon-like carbon fibers were obtained. In our experiment, methanol was used as the carbon source and the nickel nitrate as the catalyst precursor. The copper plate was used as the substrate. M. M. Wilson et al. also adopted flame method, but their setup is complex. From the view of realizable application, our method is more adaptive. This study has significances for fundamental investigation and has a promising of industrial application.