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ChemInform Abstract The voltammetry profiles obtained for Te in aqueous H2SO4 at glassy carbon and Au working electrodes show a remarkable degree of sensitivity to the electrode surface. A set of waves attributable to the direct 6e-reduction of HTeO2+ to H2Te, and a cathodic pre-wave associated with the catalytic deposition of Te (0), are observed at the Au surface, whereas these features are absent at the glassy carbon electrode. On the other hand, the 2e-reduction of Te(0) to H2Te occurs in a similar fashion at the two electrode surfaces. Evidence for a follow-up homogeneous reaction chemistry involving HTeO2+ and H2Te is presented. The described results demonstrate the applicability of oscillating quartz crystal microgravimetry for studies of the electrodeposition of semiconductors. Using a combination of the voltammetric and microgravimetric data, an internally consistent mechanistic scheme for the aqueous electrochemistry of Te is presented.

The cathodic electrodeposition chemistry in the ternary Hg-Cd-Te system was studied using hydrodynamic voltammetry in conjunction with cyclic photovoltammetry, x-ray diffraction (XRD) analyses, and optical measurements. The binary Hg-Te system was studied first, as a prelude to the more complex ternary case. An H2SO4 electrolyte matrix was used in these studies. The Hg stripping waves observed on the return scan at the disk were altered in shape when the disk was scanned into the Te 4+ ---> Te ~ and Te 4 § --> Te 2-regimes on the forward sweep. Monitoring of the ring response both at 1.40V[vs. standard calomel electrode (SCE)] and 0 V permitted selective detection of Hg and Te species generated at the disk.

In this paper we study the kinetics of Li adsorption on the SrTiO3(100) (STO(100)) surface at room temperature (RT). The study took place in an ultra-high vacuum (UHV) by low-energy electron diffraction (LEED), Auger electron spectroscopy (AES), electron energy-loss spectroscopy (EELS), temperature-programmed desorption (TPD) and work function (WF) measurements. At low Li coverage (θ<0.5 ML), Li adsorbs as isolated atoms, whereas at higher coverage it intermixes with the oxygen of the substrate and/or it intercalates into the substrate. The sticking coefficient of Li on STO(100) is constant. The lithium remains in a non-metallic state on the surface. After heating at 1100 K, part of the Li remains on the surface.