Presented work studies the relation between kinetics of metal deposition via surface limited redox replacement (SLRR) of underpotentially deposited (UPD) monolayer (ML) and experimental parameters of reaction solution such as meal ions concentrations and supporting electrolyte concentration. The model system is Au deposition on Au(111) via SLRR of Pb UPD ML. The rate constant of the SLRR reaction for different solution designs is determined from temporal change of electrode surface reflectivity and from the open circuit potential transients' analysis. The obtained results show clearly that reaction kinetics of metal deposition via SLRR of UPD ML is significantly affected by the design of the reaction solution i.e. the UPD metal ion, depositing metal ion, and supporting electrolyte concentrations. The ten-fold change of concentration of either solution parameter produces approximately the same change in the value of the rate constants. The presented results have fundamental importance for the future development and application of the metal deposition via SLRR of UPD ML. They offer a link between the reaction solution design and expected trend in SLRR reaction rate, which transposes to successful control of deposition flux, nucleation density and resulting morphology of the deposit. Deposition via Surface Limited Redox Replacement (SLRR) of underpotentially deposited (UPD) monolayer (ML)1 has gained a lot of attention and applications in last two decades.2-4 The main idea is to use an UPD ML as sacrificial material to reduce/deposit a more noble metal (SLRR reaction i.e. galvanic displacement). The basic stoichiometry of the SLRR reaction and deposition process is shown by Equation 1.Here, M and P and S(h,k,l) stand for UPD metal/ion, depositing metal/ion and substrate, while m + /m and p + /p represent the oxidation state of M and P metal ions and corresponding stoichiometry coefficients. Over the years, several experimental protocols for deposition via SLRR of UPD ML have been developed. The first and the basic one, 1,6 involves formation of the UPD ML of M on the substrate S(h,k,l), (potential controlled step) and then subsequent immersion of M UPD /S(h,k,l) into a separate reaction solution where SLRR occurs and deposition of P takes place at open circuit (sample shuffling approach). The second protocol involves the stagnant substrate but sequential application of potential control in solution for UPD ML formation and then application of solution for SLRR reaction and deposition of P at open circuit (solution shuffling approach 7 ). The most recent development has introduced a "one-solution, one-cell" experimental design. 8,9 In this case, the same solution serves for UPD ML formation and subsequent SLRR reaction at open circuit potential. This protocol assumes a sequence of potential controlled step, where co-deposition of UPD ML of M with small amount of P occurs, and the open circuit step, where SLRR reaction and deposition of P proceeds. The very details of these three protocols and their applications hav...

UV-cured caprolactone-based polyurethane acrylate (PUA) polymer blend electrolytes were prepared and characterised. To develop polymer electrolytes suited to ambient temperature, an ionically-conductive and reliable polymer electrolyte based on urethane acrylate resins synthesised from a fluorine-containing di-functional oligomer 6F ethoxylated diacrylate, a di-functional reactive diluent 1,6-hexanediol diacrylate for adjusting the viscosity, and a radical photo-initiator doped with a mixture of lithium salts were used. Free-standing flexible electrolyte films were prepared by UV-curing via free-radical photopolymerisation. The performance of the lithium polymer cell system (Li/PE(F4)/LiCoO2) was determined by electrochemical impedance spectroscopy, cyclic voltammetry, a galvanostatic recurrent differential pulse, chronocoulometry and chronoamperometry. The electrolyte with optimal amounts of fluorine-containing oligomer and optimal salt mixture content exhibited enhanced conductivity, showing a conductivity of 1.00 × 10 −4 S cm −1 at ambient temperature. The specific capacity, specific energy and specific power of a Li/PE(F4)/LiCoO2 cell were also determined.

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Electrochemical reduction of two recently synthesized pyrimidine compounds 1-amino-5-benzoyil-4-phenyl-1H-pyrimidine-2-one (I), and 1-amino-5-benzoil 4-phenyl-1H-pyrimidine-2-thione (II) were investigated by cyclic volatmmetry at a hanging mercury drop electrode in aqueous methanol (36 % v/v) and in non-aqueous methanol. Aseries of cathodic peaks without the corresponding anodic peaks were observed for I. As the pH of the solution was increased some of the cathodic peaks overlapped resulting in the loss of the previously observed peaks. For II, three cathodic peaks and one anodic peak were observed in addition to those observed for I. The peak potentials shifted in the negative direction with increasing pH. This shift was measured over a large pH range (1.80 ? 12.30) to determine the pKa values of the compounds. The acidity constants related to the amino groups were 4.80 and 9.80 for I and 5.50 and 9.80 for II. Athiol-thione tautomerization was observed for II which was more pronounced in the non-aqueous methanol medium. The pK values for both protonation and deprotonation of the thiocarbonyl group were also determined. The pK values were 5.80 and 9.80 for protonation and deprotonation in aqueous methanol and 6.80 and 10.80 in non-aqueous methanol.

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