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Tin sulfide thin films, typically 350 nm thick, were deposited on SnO2:F -coated transparent conductive oxide glass substrates by pulse electrodeposition. The applied potentials were Von=−0.9V and Voff=0.1V vs saturated calomel electrode with pulse on/off durations of 10 s. The films crystallized in the orthorhombic structure corresponding to SnS (herzenbergite), with grain size varying in the range from a few nanometers to more than 100 nm. X-ray diffraction analysis shows an average size of 12 nm; however, scanning electron microscopy and transmission electron microscopy images show the presence of large crystallites with well-developed facets along with agglomerations of smaller crystallites. Estimation of the bandgap from the optical spectra of these films showed absorption due to direct transition occurring at 1.3 eV. Elemental compositions of these SnS samples determined using energy dispersive X-ray spectroscopy were 51.4 and 48.5%, respectively, for Sn and S. Raman spectra suggested the presence of traces of Sn2normalS3 and SnS2 . The surface analysis by X-ray photoelectron spectroscopy showed the presence of traces of metallic Sn. The films are photosensitive with a dark resistivity 106Ωcm .

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The evolution of MgAl layered double hydroxides (LDHs), prepared by the sol-gel method, throughout the synthesis-crystallization-calcination-reconstruction process is thoroughly studied and compared to a coprecipitated analogue. X-ray diffraction and transmission electron microscopy provide useful information about crystallinity and morphology of the samples. It was found that crystal sizes do not necessarily decrease after calcination-reconstruction. Furthermore, aluminum coordination is studied by 27 Al MAS nuclear magnetic resonance and by X-ray photoelectron spectroscopy (XPS), revealing significant differences in the relative populations of tetrahedral aluminum in the surface and the bulk of the calcined sol-gel LDHs. Magnesium and oxygen structural environments are also studied by XPS. A possible correlation between crystal sizes of calcined LDHs and the amount of O 2surface species is discussed. Differences in the structural environment of magnesium in the as-synthesized and the reconstructed LDH are presented and analyzed.