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Nanosilicas can disperse single-wall carbon nanotube (SWCNT) in aqueous solution efficiently; SWCNTs are stably dispersed in aqueous media for more than 6 months. The SWCNT dispersing solution with nanosilica can produce highly conductive transparent films which satisfy the requirements for application to touch panels. Even multiwall carbon nanotube can be dispersed easily in aqueous solution. The highly stable dispersion of SWCNTs in the presence of nanosilica is associated with charge transfer interaction which generates effective charges on the SWCNT particles, giving rise to electrostatic repulsion between the SWCNTs in the aqueous solution. Adhesion of charged nanosilicas on SWCNTs in the aqueous solution and a marked depression of the S11 peak of optical absorption spectrum of the SWCNT with nanosilicas suggest charge transfer interaction of nanosilicas with SWCNT. Thus-formed isolated SWCNTs are fixed on the flexible three-dimensional silica jelly structure in the aqueous solution, leading to the uniform and stable dispersion of SWCNTs.

ZnO nanophosphors with a diameter of 7 -50 nm have been fabricated under an oxygen gas atmosphere at room temperature by evaporating ZnO powder or Zn targets using pulsed laser ablation. The size and uniformity of ZnO nanophosphors strongly depend on oxygen gas pressure. Results of cathodoluminescence analysis show strong ultraviolet, blue, green, and greenyellow emissions from ZnO nanophosphors excited by a $150 eV low-energy electron beam emitted from carbon nanotubes, depending upon the target material and oxygen gas pressure. Ultraviolet, blue, green, and green-yellow emissions can be attributed to the transitions from the conduction band to the valence band, the Zn i level to the V Zn level or the valence band, the V O level to the valence band, and the Zn i level to the O i level, respectively.

The graphite encapsulated iron nanoparticles were fabricated by using arc discharge method. The synthesized nanoparticles were pre-treated by an inductively coupled RF Ar plasma and then post-treated by NH 3 plasma under various gas pressures and treatment times. Analyses of XPS spectra have been carried out to study the effect of the plasma treatment on the surface modification of nitrogen-containing groups. The morphological changes of the particles surface by plasma treatment have also been analyzed by using HR-TEM. Present results show that the highest values of N/C atomic ratio of 4.4 % is obtained by applying 10 min of Ar plasma pre-treatment and 2 min of NH 3 plasma post treatment conducted in RF power of 80 Watt and gas pressure of 50 Pa.

We report a bimetallic Zn/Al complex as an efficient inorganic dispersant for SWCNT, synthesized from Zn(CH3COO)2 and Al(NO3)3. The Zn/Al complex shows more than four times greater efficiency at dispersing SWCNT than widely used surfactants (CTAB and SDS). Besides remarkable dispersibility, the Zn/Al complex does not foam upon any shaking treatment and it can be used just after quick dissolution of the powdered form, which is a marked advantage over surfactants. The Zn/Al complex, containing amorphous Al(CH3COO)3 and a complex of Zn 2+and NO 3 − ions, should have a unique dispersion mechanism, differing from the surfactants.Al(CH3COO)3 has higher affinity for SWCNT than ions, adsorbing onto their surface in the first layer and attracting Zn 2+ and NO 3 − ions. Charge transfer interactions between the Zn/Al complex and SWCNT as evidenced by optical absorption spectroscopy should induce a charge on SWCNT; the zeta potential of such coated SWCNT was +55 mV, which is in agreement with the high stability of SWCNT in water. Hence, the Zn/Al complex can widen the applications of SWCNT to various technologies such as the transparent and conductive films, as well as high performance composite polymers.