ChemInform Abstract: Chemical and Electrochemical Behavior in Molten Alkali Hydroxides. Part 3. Chemistry of Tin(II) and (IV) in the NaOH‐KOH Eutectic Mixture and in Pure NaOH.

Abstract

013ChemInform Abstract In molten hydroxides, Sn(II) is unstable and is converted to Sn(IV) at a rate which depends on the temp. and on the acid-base properties of the melts. The oxidation of SnO occurs either directly in the solid phase or after dissolution as SnO22-. Basic conditions promote the liquid phase oxidation. In the NaOH-KOH eutectic mixture, Sn(IV) dissolves as SnO32-, which is insoluble in acidic melts and precipitates as Na2SnO3 upon acidification of a basic solution. In basic melts, Sn(IV) dissolves as SnO44-and Na4SnO4 precipitates from saturated solutions.

Synthesis and Characterization of Ti1−xSnxO2 Nanoparticles and Nanotubes and their Photovoltaic Properties as Dye-Sensitized Solar Cell Photoelectrodes

“…Taking into account the formation mechanism of TiO 2 nanotubes, 11,12 the Sn ion removed by the Na ion might not be able to bind with the Ti ion again, because Ti 1− x Sn x O 2 particles in the strong basic solution (10 M NaOH) may become an amorphous, layered compound, and a layer separation process may occur during washing with deionized water and HCl. Also, Sn ion is more unstable in an NaOH solution rather than in a slightly acidic solution (hence in low concentrations of HCl solution), and tends to exist as a dissolution form of SnO 2 2− or SnO 3 2− 22 . Consequently, the dissolved Sn ion may get washed off during the ion exchange process.…”