Journal of Nano Research Vol. 11

Abstract: The effect of surface modification by nanoparticles of metal compounds was investigated by means of gas and vapor adsorption analysis. The surface of activated carbon fiber cloths was modified by loading of Li2CO3 and MgO nanoparticles. The particles on the carbon surface played as initial adsorption site of water molecules, leading to the promotion of micropore filling without diminishing the micropore volume of the porous carbon supports. The increasing characteristic adsorption energy suggested some interaction between methane molecules and the particles.

Abstract: The temperature and particle size dependence of the holewidths for the 7F0 → 5D0 transition of Eu3+ ions in Eu2O3 are calculated and compared with experiment. The calculation is able to describe the effect of nanocrystal vibrational modes on the dephasing of the electronic states of probe ions. The nanocrystal was treated as an elastically isotropic sphere from which the acoustic phonon displacements and phonon spectrum were calculated. Then we applied this to the temperature and size dependencies of the electron-phonon interaction. Also the vibrational modes in nanocrystals are discussed.

Abstract: The success of the developed nano-engineering technology will lead to a redefinition of optical device manufacturing and integration and the functional and economic displacement of traditional bulk-optics devices. The discovery of nonlinear optical properties of the Carbon Nanotube (CNT) has paved the way for the research and development of high optical non linearity in CNT based nano optical fiber. In this paper, a novel structure of our proposed high optical non linearity CNT based nano optical fiber has been studied. In addition, a mathematical analysis on a high third-order optical non linearity of CNT based nano optical fiber has been done.

Abstract: Hydroxyapatite (HAp) is an important bioactive ceramic that possessing beneficial biocompatibility and osteoconductivity resulting in bonding to human bone tissues. The dry mechanochemical process is widely used to prepare nanometer HAp. However, little research has been carried out concerning the correlation between adding alumina and the structural changes during the mechanochemical process. In this research, special attention was paid to the effect of alumina additive on the crystallite size and lattice strain of nanocrystalline HAp. Characterization was accomplished by using powder X-ray diffraction (XRD). The obtained data demonstrated that the diffraction lines corresponding to the HAp phase became broad and weak with increasing alumina additive. In fact, the nanocrystalline HAp with high crystallinity degree can be synthesized in the proper amounts of alumina additive via mechanochemical method. Furthermore, an increase of alumina additive led to increase in lattice strain and decrease in size of the powder grain.

Abstract: Ga doped SiO2 nanosized particles have been synthesized using a reverse micelle technique combined with metal alkoxide hydrolysis and condensation. The size of the particles and the thickness of the coating can be controlled by manipulating the relative rates of the hydrolysis and condensation reactions of tetraethyl orthosilicate(TEOS) within the micro-emulsion. The average size of synthesized Ga doped SiO2 nanoparticles were about in the size range of 10-15 nm and Ga particles 2-5 nm. The effects of synthesis parameters, such as the molar ratio of water to TEOS, and the molar ratio of water to surfactant, are discussed.

Abstract: The origin of enhanced intercalation of Li-ions into TiO2-B is being examined using first principles density functional calculations. Using advanced simulation techniques, we built a comprehensive description of Li-intercalation into TiO2-B and demonstrate that it acts as a capacitor at [Li]/[Ti] ≤ 0.5, while at higher concentrations the insertion capacity is limited by Li self-diffusion.