Pervaporation is an important alternative membrane separation process compared to the distillation technique, and a relatively high separation factor is required to lower the energy demand. Solution processable nanocomposite membranes prepared by incorporating functionalized graphene sheets (FGS) loaded in various concentrations into the chitosan matrix have been employed for the pervaporative dehydration of ethanol and isopropanol. Incorporation of FGS leads to an increase of surface hydrophilicity of the chitosan membranes along with an increase in membrane tortuosity that was favorable to the selective permeation of water molecules. The nanocomposite membrane containing 2.5 wt % FGS gave the highest selectivities of 7781 and 1093 for isopropanol−water and ethanol−water mixtures, respectively, when tested for 10 wt % water-containing feed mixture. Membranes were characterized by wide-angle XRD, SEM, contact angle, and optical profilometry techniques. The Flory−Huggins theory was employed to estimate the polymer−solvent interaction parameter. Diffusion values and Arrhenius activation energy parameters provided quantitative evidence for the observed increase in water selectivity at higher loading of FGS.

The homogeneously aligned liquid crystal display on Ta2O5 via ion beam (IB) irradiation was first embodied with controllability of pretilt angle depending on incident angle of the IB. As a result of x-ray photoelectron spectroscopic analysis, the intensity of Ta–O and O–Ta bondings as a function of incident angle behaved reversely with the pretilt angle and the lowest amplitude was observed at 45°. It revealed that the creation of pretilt angle was attributed to the irradiation of the IB by breaking Ta–O and O–Ta bonding so orientational order was generated by directional IB. Comparable electro-optical characteristics to rubbed polyimide were also achieved.

The surface modification characteristics of liquid crystal (LC) alignment layers irradiated with various argon (Ar) ion beam (IB) energies were investigated as a substitute for rubbing technology. Various pretilt angles were created on the IB-irradiated polyimide (PI) surfaces after IB irradiation, but the Ar ions did not alter the morphology on the PI surface, indicating that the pretilt angle was not due to microgrooves. The chemical bonding states of the IB-irradiated PI surfaces were analyzed in detail by x-ray photoelectron spectroscopy to verify the compositional behavior for the LC alignment. Chemical structure analysis showed that the alignment ability of LCs was due to the preferential reorientation of the carbon network due to the breaking of C=O double bonds in the imide ring parallel to the incident IB direction. The potential of applying nonrubbing technology to display devices was further supported by the superior electro-optical characteristics compared to rubbed PI.

Electro-optic performance of a liquid-crystal (LC) system is enhanced by TiO(2) nanoparticle dispersed in nematic liquid crystal (NLC). The 2.5 V threshold voltage of LC for device operation is lowered to 0.5 V through TiO(2) nanoparticle mixing up to 2 wt.%. To characterize the shape and size distribution of the nanoparticles, high-resolution transmission electron microscopy is employed. Transmittance spectra for the TiO(2) dispersed LC structure and nondispersed LC structure showed that transparency of the TiO(2) dispersed LC is similar to that of pure liquid LC.

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