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Atomically resolved scanning tunnelling microscopy (STM) images have been obtained on ultrathin films of CeO 2 (111) supported on Pt(111). The ultrathin films were grown in two ways, by reactive deposition in an oxygen atmosphere and by postoxidation of Ce/Pt surface alloys. STM results are compared with previously reported high-temperature STM and noncontact atomic force microscopy (NC-AFM) images of the native CeO 2 (111) surface. The similarity between these images is striking and allows a number of defects and adsorbates in our ultrathin film to be assigned. Moreover, the similarity in structure between the native oxide and the ceria ultrathin film indicates that it is an excellent topographic mimic of the native oxide.

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Electron bombardment from a filament as well as voltage pulses from a scanning tunnelling microscope tip have been employed to modify the surface of TiO2(110). Individual H atoms are selectively desorbed with electrical pulses of +3 V from the scanning tunnelling microscope tip, whilst leaving the oxygen vacancies intact. This allows us to distinguish between oxygen vacancies and hydroxyl groups, which have a similar appearance in scanning tunnelling microscopy images. This then allows the oxygen vacancy-promoted dissociation of water and O2 to be followed with the microscope. Electrical pulses between +5 and +10 V induce local TiO2(110)1 × 2 reconstructions centred around the pulse. As for electron bombardment of the surface, relatively low fluxes increase the density of oxygen vacancies whilst higher fluxes lead to the 1 × 2 and other 1 × n reconstructions.

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In this work, polymer electrolytes have been prepared by doping starch with lithium iodide (LiI). The incorporation of 30 wt% LiI optimizes the room temperature conductivity of the electrolyte at (1.83 ± 0.47) × 10 −4 S cm −1. Further conductivity enhancement to (9.56 ± 1.19) × 10 −4 S cm −1 is obtained with the addition of 30 wt% glycerol. X-ray diffraction analysis indicates that the conductivity enhancement is due to the increase in amorphous content. The activation energy, E a , of 70 wt% starch-30 wt% LiI electrolyte is 0.26 eV, while 49 wt% starch-21 wt% LiI-30 wt% glycerol electrolyte exhibits an E a of 0.16 eV. Dielectric studies show that all the electrolytes obey non-Debye behavior. The power law exponent s is obtained from the variation of dielectric loss, ε i , with frequency at different temperatures. The conduction mechanism of 70 wt% starch-30 wt% LiI electrolyte can be explained by the correlated barrier hopping model, while the conduction mechanism for 49 wt% starch-21 wt% LiI-30 wt% glycerol electrolyte can be represented by the quantum mechanical tunneling model.