CuxO-TiO2 (x = 1, 2) nanomaterials are synthesized on polycrystalline Ti substrates by a convenient chemical vapor deposition (CVD) approach, based on the initial growth of a CuxO matrix (at 400 and 550 °C for x = 1 and 2, respectively) and the subsequent overdispersion of TiO2 at 400 °C. All CVD processes are carried out in an oxygen atmosphere saturated with water vapor. The obtained systems are investigated by means of glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), field emission-scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and electrochemical experiments. Galvanostatic charge/discharge measurements indicate that Cu2O-TiO2 nanomaterials exhibit very attractive high-rate capabilities (∼400 mA h g(-1) at 1 C; ∼325 mA h g(-1) at 2 C) and good stability after 50 operating cycles, with a retention of 80% of the initial capacity. This phenomenon is mainly due to the presence of TiO2 acting as a buffer material, i.e., minimizing volume changes occurring in the electrochemical conversion. In a different way, CuO-TiO2 systems exhibit worse electrochemical performances as a consequence of their porous morphology and higher thickness. In both cases, the obtained values are among the best ever reported for CuxO-based systems, candidating the present nanomaterials as extremely promising anodes for eventual applications in thin film lithium batteries.

The design and assembly of suitable nanosystems are key issues in the development of smaller and more efficient lithium batteries. To this regard, cobalt oxides possess very favorable properties for use as negative electrode materials. In this work, we describe a convenient synthesis route to cobalt oxide nanomaterials (both single- and mixed-phase CoO and Co3O4) supported on Ti. The systems are grown by chemical vapor deposition starting from an innovative second-generation molecular source, Co(hfa)2·TMEDA (hfa ) 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate, TMEDA ) N,N,N′,N′-tetramethylethylenediamine). Controlled variations of the substrate temperature and O2 pressure in the reaction atmosphere enabled tailoring both the phase composition and the system morphology. The electrochemical properties of the obtained nanosystems were evaluated by galvanostatic measurements and impedance spectroscopy. The results showed excellent cycling performances and very high specific capacity values, offering attractive perspectives for the use of the present systems as advanced anode materials in Li-ion batteries

The presence of NO9x) gases (NO+NO2) in the atmosphere is a major concern of society because of their associated adverse and harmful effects. In order to remove the NO(x) gases from the air, photocatalysis arises as an innovative and promising technique. Through the use of photochemical oxidation processes the NO and NO2 gases are oxidised to NO3- form and thus removed from the air. In recent years new nanomaterials are being developed by researchers with the aim to enhance their photocatalytic activity to combat the NO(x) pollution. The main focus is devoted to preparing new TiO2 based compounds with the highest specific surface area (SSA), different morphology and chemical modifications. In order to increase the SSA, different substrates were used to disperse the TiO2 nanoparticles: organic and carbon fibres, mesoporous materials, clays composites and nanoporous microparticles. In the other hand, high photocatalytic performances were obtained with nanotubes, self-orderer nano-tubular films and nanoparticles with the lowest size. Conversely, when TiO2 is doped with ions the oxide exhibited a better photocatalytic performance under visible light, which is related to the creation of intermediate energy states between the conduction band and the valence band. Alternatively, visible light photocatalysts different from titanium oxide have been studied, which exhibit a good De-NO(x) efficiency working under λ > 400 nm visible light irradiation.

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