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A suitably sized charge transfer probe of an elongated geometry can induce the formation of R-cyclodextrin nanotubular suprastructures, a rare event because of size restriction of the host. The specific molecular structure is found to be responsible only for the 1:2 guest-host complex formations. No evidence of the formation of the 1:1 complex is found. Steady-state fluorescence anisotropy and atomic force microscopy show that the nanocomposites club with other such species very efficiently to form nanotubes and nanoclusters because of primary interactions through hydrogen bonding and develop nanotubular suprastructures due to secondary interactions. The degree of formation of the suprastructures is found to be very much controlled by the probe concentration. In aqueous environment, 2 µM is observed to be the best concentration for the fluorophore form of large rodlike aggregates. Concentrations as low as 1 µM and as high as 4 µM induce the formation of relatively smaller structures. The findings encourage the applications of cyclodextrin nanotubular clusters toward nanotechnology and pharmaceutical research. The concentration dependent phenomenon will dictate the drug dosage as also the extent of formation of the nanostructures in the formation of insulated nanowires. The work is purely indicating the anchoring capability of the used molecule to form nanotubular R-CD suprastructures which otherwise does not form so frequently.

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A solid polymer electrolyte system based on poly(vinyl alcohol) (PVA) complexed with potassium chloride (KCl) salt was prepared by using solution cast technique. The complexation of KCl salt with the polymer was confirmed by X‐ray diffractrometer and Fourier transform infrared spectroscopy. Differential scanning calorimetry was used to determine the melting temperatures and crystallinity of the pure PVA and complexed films. Ionic conductivities of the electrolytes have been determined by AC impedance studies in the temperature range 303–373 K. The conductivity was found to increase with the increase in dopant concentration and temperature. Transference number data suggests that the charge transport in this polymer electrolyte system is mainly due to ions. Optical absorption studies were made in the wavelength range 200–800 nm on pure and KCl doped PVA films. The absorption edge, direct band, and indirect band gap values were evaluated. It was found that the energy gaps and band edge values shifted to lower energies on doping. Electrochemical cells were fabricated with the configuration of K/(PVA + KCl)/(I2 + C + electrolyte) and discharge characteristics were studied under a constant load of 100 kΩ. Various cell parameters, such as open circuit voltage, short circuit current, power density, and energy density were determined. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers

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