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The synthesis of ZnO particles from Zn(CH3Co2) in 2-propanol as a function of the concentration of water is reported. Particles with diameters of 3-5 nm are formed depending on time, temperature, and water concentration.

The study demonstrated that alternative redox mediators could be successfully used within dye-sensitized solar cells comprised of a nanocrystalline SnO(sub 2) electrode. Photocurrent efficiencies and cell voltages were larger using the alternative redox mediator (SeCN)2/SeCN(super -) compared to I(sub 3)(super -)/I(super -) for all three sensitizers.

The potential distribution at the semiconductor/solution interface under weak depletion and accumulation conditions were investigated. The applied potential is partitioned between the space charge layer in the semiconductor and the Helmholtz layer on the solution side of the interface. Under deep depletion conditions, a change in the applied potential usually appears across the space charge layer and the band bending can be determined using the Mott-Schottky relation. Under conditions of weak depletion, determination of band bending is not straightforward.

A study was conducted to examine impedance responses associated with surface states at semiconductor/solution interfaces. A number of model predictions were considered in the study to serve as diagnostic features for different cases of states. A kinetic approach was carried out to compute the complete impedance response resulting from electronic surface state processes. Results indicated that critical rate constants can be obtained from the frequency dependence of impedance elements.

A study was conducted to analyze the sol-gel synthesis of carbon/ceramic composite electrodes with an interconnected network of carbon particles. Films of the silica-based gel featured pore sizes smaller than 1 micron. Experimental results indicated that the electrodes were porous and electrically conductive. Findings also showed that more than half of the carbon surface area was accessible electrochemically.

Research was conducted to examine the energetics of the silicon/solution interface over a wide potential range from depletion to accumulation using potential modulated microwave reflectivity. Results indicate that for the system the partitioning of the applied potential between the Helmholtz layer and the space charge layer dominate the electrochemical response at potentials negative of the flatband potential.

A numerical model is proposed that obtains the electrical output of dye-sensitized solar cells from microscopic parameters. The current-voltage curve, the dependence of the short-circuit current and the open-circuit voltage on the light intensity are determined within the assumptions of the model.

The fabrication and characterization of n-type 4H-SiC/Ni contacts formed by electrodeposition from nickel sulfate solutions is reported. Nickel deposition on n-type 4H-SiC is characterized by nucleation followed by diffusion-limited growth of three-dimensional clusters.

The synthesis of ZnO nanoparticles from Zn(CH3CO2)(sub 2), ZnBr2, and Zn(ClO4)(sub 2) in 2-propanol is reported. The rate constant for coarsening at constant temperature increases in the order of Br(super -) < CH3CO2(super -) < ClO4(super -) indicating that the rate is dependent on anion adsorption.

The growth kinetics of TiO2 nanoparticles synthesized from aqueous solution is reported using titanium(IV) isopropoxide as precursor. It was found that the number of primary particles per secondary particle increases with time, and the percentage of primary particles present in the colloid decreases with increasing temperature.

The pseudohalogens redox couples are evaluated to determine the effect of the equilibrium potential of the redox couple on the energetics and kinetics of dye-sensitized TiO2 photoelectronchemical cells. The results revealed that selecting a redox couple with a more positive equilibrium potential does not necessarily translate into an increase of the open circuit potential.

The mechanisms of particle growth for four oxides and oxyhydroxides from homogenous solution, which consist of hematite (Fe2O3) synthesized by aging an acidic ferric chloride solution, feroxihite (FeOOH) by oxidation of a ferrous chloride solution, anatase (TiO2) by sol-gel synthesis and hydrothermal aging, and heterogenite (CoOOH) by oxidation of cobalt (II) chloride solution is examined. Findings suggest that the aggregation processes dominate the solution-based growth of several metal oxide / oxyhydroxide particles.