2013 |
Glynn, C; Thompson, D; Paez, J; Collins, G; Benavente, E; Lavayen, V; Yutronic, N; Holmes, J D; González, G; O'dwyer, C Large Directional Conductivity Change in Chemically Stable Layered Thin Films of Vanadium Oxide and a 1d Metal Complex Artículo de revista Journal of Materials Chemistry C, 1 (36), pp. 5675-5684, 2013, ISSN: 2050-7526. Resumen | Enlaces | BibTeX | Etiquetas: charge hybrid intercalation, low-temperature, materials, mechanism, nanocomposites, nanostructures, sol-gel, transport, v2o5 @article{RN136, title = {Large Directional Conductivity Change in Chemically Stable Layered Thin Films of Vanadium Oxide and a 1d Metal Complex}, author = { C. Glynn and D. Thompson and J. Paez and G. Collins and E. Benavente and V. Lavayen and N. Yutronic and J.D. Holmes and G. Gonz\'{a}lez and C. O'dwyer}, url = {/brokenurl#<Go to ISI>://WOS:000323578000011}, doi = {10.1039/c3tc31104j}, issn = {2050-7526}, year = {2013}, date = {2013-01-01}, journal = {Journal of Materials Chemistry C}, volume = {1}, number = {36}, pages = {5675-5684}, abstract = {Electroactive hybrid and layered oxides and related materials where the inorganic phase is the host, offering the conductivity characteristics of semiconductors, have been used in thin film transistors and related electronic devices where the host-guest interaction offered conductivity with improved processability. We describe the synthesis and characterization of a nanocomposite that shows large conductivity anisotropy when deposited as a thin film. We prepared the material by inserting quasi 1-dimensional potassium tetracyanoplatinate metal complexes with insulating electrical properties in between stacked nanosheets of vanadium oxide xerogels. Detailed structural and compositional analysis using transmission electron microscopy and X-ray photoelectron spectroscopy confirms that the hybrid material forms from a topotactic reaction and the framework of the layered host oxide structure is maintained. The hybrid film demonstrates a similar to 1000-fold conductivity change between transport parallel and perpendicular to the film at room temperature. Temperature dependent transport measurements confirm Ohmic conduction perpendicular to the stack and small polaron hopping conduction parallel to the layering direction of the film. The conductivity anisotropy and simple synthesis demonstrate that nanostructured layered hybrids can provide alternative materials for thin film complementary logic and resistive memory.}, keywords = {charge hybrid intercalation, low-temperature, materials, mechanism, nanocomposites, nanostructures, sol-gel, transport, v2o5}, pubstate = {published}, tppubtype = {article} } Electroactive hybrid and layered oxides and related materials where the inorganic phase is the host, offering the conductivity characteristics of semiconductors, have been used in thin film transistors and related electronic devices where the host-guest interaction offered conductivity with improved processability. We describe the synthesis and characterization of a nanocomposite that shows large conductivity anisotropy when deposited as a thin film. We prepared the material by inserting quasi 1-dimensional potassium tetracyanoplatinate metal complexes with insulating electrical properties in between stacked nanosheets of vanadium oxide xerogels. Detailed structural and compositional analysis using transmission electron microscopy and X-ray photoelectron spectroscopy confirms that the hybrid material forms from a topotactic reaction and the framework of the layered host oxide structure is maintained. The hybrid film demonstrates a similar to 1000-fold conductivity change between transport parallel and perpendicular to the film at room temperature. Temperature dependent transport measurements confirm Ohmic conduction perpendicular to the stack and small polaron hopping conduction parallel to the layering direction of the film. The conductivity anisotropy and simple synthesis demonstrate that nanostructured layered hybrids can provide alternative materials for thin film complementary logic and resistive memory. |
2012 |
Lopez-Cabana, Z; Navas, D; Benavente, E; Santa-Ana, M A; Lavayen, V; González, G Hybrid Laminar Organic-Inorganic Semiconducting Nanocomposites Artículo de revista Molecular Crystals and Liquid Crystals, 554 , pp. 119-134, 2012, ISSN: 1542-1406. Resumen | Enlaces | BibTeX | Etiquetas: nanocomposites, semiconductors, v2o5, zno @article{RN79, title = {Hybrid Laminar Organic-Inorganic Semiconducting Nanocomposites}, author = { Z. Lopez-Cabana and D. Navas and E. Benavente and M.A. Santa-Ana and V. Lavayen and G. Gonz\'{a}lez}, url = {/brokenurl#<Go to ISI>://WOS:000302299300014}, doi = {10.1080/15421406.2011.633852}, issn = {1542-1406}, year = {2012}, date = {2012-01-01}, journal = {Molecular Crystals and Liquid Crystals}, volume = {554}, pages = {119-134}, abstract = {Hybrid two-dimensional nanocomposites of transition metal semiconductors based on molybdenum disulfide, zinc oxide, and vanadium pentoxide, in which ultra-thin sheets of the inorganic component are stabilized by insertion into a bilayer of organic amphiphiles, are described. The resulting solids are commensurate species with characteristic stoichiometries, extremely high aspect ratio, and large organic-inorganic interfaces. Synthesis procedures and changes in the properties of the nanocomposites with respect to those of their components, depend on the structural nature of the pristine semiconductor. Derivatives of the laminar semiconductor MoS2 are obtained by quasi-topotactic intercalation of amphiphiles into the layered inorganic matrix, being changes in the properties mainly associated to guest-host charge transfer without altering significantly the electronic structure of the sulfide. In the case of the structurally isotropic ZnO bottom-up sol-gel synthesis procedures, it is necessary to use amphiphiles as templates, producing the two dimensional confinement with significant changes in the band gap of the semiconductor. Vanadium oxide, because of bonding asymmetry, may be easily intercalated. However due to its low laying conduction band, this leads to mixed valence species. Beyond size and dimension induced bang-gap changes, the optical properties of the products, as appreciated in their absorption and emission spectra, are in general qualitatively similar to those of pristine semiconductors.}, keywords = {nanocomposites, semiconductors, v2o5, zno}, pubstate = {published}, tppubtype = {article} } Hybrid two-dimensional nanocomposites of transition metal semiconductors based on molybdenum disulfide, zinc oxide, and vanadium pentoxide, in which ultra-thin sheets of the inorganic component are stabilized by insertion into a bilayer of organic amphiphiles, are described. The resulting solids are commensurate species with characteristic stoichiometries, extremely high aspect ratio, and large organic-inorganic interfaces. Synthesis procedures and changes in the properties of the nanocomposites with respect to those of their components, depend on the structural nature of the pristine semiconductor. Derivatives of the laminar semiconductor MoS2 are obtained by quasi-topotactic intercalation of amphiphiles into the layered inorganic matrix, being changes in the properties mainly associated to guest-host charge transfer without altering significantly the electronic structure of the sulfide. In the case of the structurally isotropic ZnO bottom-up sol-gel synthesis procedures, it is necessary to use amphiphiles as templates, producing the two dimensional confinement with significant changes in the band gap of the semiconductor. Vanadium oxide, because of bonding asymmetry, may be easily intercalated. However due to its low laying conduction band, this leads to mixed valence species. Beyond size and dimension induced bang-gap changes, the optical properties of the products, as appreciated in their absorption and emission spectra, are in general qualitatively similar to those of pristine semiconductors. |
2013 |
Large Directional Conductivity Change in Chemically Stable Layered Thin Films of Vanadium Oxide and a 1d Metal Complex Artículo de revista Journal of Materials Chemistry C, 1 (36), pp. 5675-5684, 2013, ISSN: 2050-7526. |
2012 |
Hybrid Laminar Organic-Inorganic Semiconducting Nanocomposites Artículo de revista Molecular Crystals and Liquid Crystals, 554 , pp. 119-134, 2012, ISSN: 1542-1406. |