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ZnO nanorod assemblies were grown by plasma-enhanced chemical vapor deposition on polycrystalline Al(2)O(3) at 200-300 degrees C, resulting in urchin-like 1-D ZnO NR arrays with a strong c-axis orientation. Their outstanding gas sensing responses and very low detection limits highlight the potential of the present systems in the production of high efficiency chemical sensors for a variety of applications

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p-Type Co(3)O(4) nanostructured films are synthesized by a plasma-assisted process and tested in the photocatalytic production of H(2) from water/ethanol solutions under both near-UV and solar irradiation. It is demonstrated that the introduction of fluorine into p-type Co(3)O(4) results in a remarkable performance improvement with respect to the corresponding undoped oxide, highlighting F-doped Co(3)O(4) films as highly promising systems for hydrogen generation. Notably, the obtained yields were among the best ever reported for similar semiconductor-based photocatalytic processes.

Interfacial oxide re-growth in thin film metal oxide III-V semiconductor systems Hafnium͑IV͒ oxide thin films were synthesized by atomic layer deposition ͑ALD͒ on Si͑100͒ substrates, using an innovative guanidinate-stabilized hafnium amide precursor, ͓Hf͑NEtMe͒ 2 ͑EtMeNC͑N i Pr͒ 2 ͒ 2 ͔. In the present work, our attention is focused on a detailed XPS characterization of a representative HfO 2 coating grown at 350°C. Beside the wide scan spectrum, detailed spectra for the O 1s, Hf 4f, Hf 4d and C 1s regions and related data are presented and discussed. The obtained results point out to the formation of HfO 2 coatings characterized by the presence of -OH groups, whose main origin is attributed to the use of water as oxidizing agent during the preparation process.

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Eight novel homoleptic tris-guanidinato complexes M[(N(i)Pr)(2)CNR(2)](3) [M = Y (a), Gd (b), Dy (c) and R = Me (1), Et (2), (i)Pr (3)] have been synthesized and characterized by NMR, CHN-analysis, mass spectrometry and infrared spectroscopy. Single crystal structure analysis revealed that all the compounds are monomers with the rare-earth metal center coordinated to six nitrogen atoms of the three chelating guanidinato ligands in a distorted trigonal prism geometry. With the use of TGA/DTA and isothermal TGA analysis, the thermal characteristics of all the complexes were studied in detail to evaluate their suitability as precursors for thin film deposition by MOCVD and ALD. The (i)Pr-Me(2)N-guanidinates of Y, Gd and Dy (1a-c) showed excellent thermal characteristics in terms of thermal stability and volatility. Additionally, the thermal stability of the (i)Pr-Me(2)N-guanidinates of Y and Dy (1a, c) in solution was investigated by carrying out NMR decomposition experiments and both the compounds were found to be remarkably stable. All these studies indicate that (i)Pr-Me(2)N-guanidinates of Y, Gd and Dy (1a-c) have the prerequisites for MOCVD and ALD applications which were confirmed by the successful deposition of Gd(2)O(3) and Dy(2)O(3) thin films on Si(100) substrates. The MOCVD grown films of Gd(2)O(3) and Dy(2)O(3) were highly oriented in the cubic phase, while the ALD grown films were amorphous.

Herein, we describe the design, fabrication and gas sensing tests of p-Co(3)O(4)/n-ZnO nanocomposites. Specifically, arrays of (001) oriented ZnO nanoparticles were grown on alumina substrates by plasma enhanced-chemical vapor deposition (PECVD) and used as templates for the subsequent PECVD of Co(3)O(4) nanograins. Structural, morphological and compositional analyses evidenced the successful formation of pure and high-area nanocomposites with a tailored overdispersion of Co(3)O(4) particles on ZnO and an intimate contact between the two oxides. Preliminary functional tests for the detection of flammable/toxic analytes (CH(3)COCH(3), CH(3)CH(2)OH, NO(2)) indicated promising sensing responses and the possibility of discriminating between reducing and oxidizing species as a function of the operating temperature.