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The interest in titanium and its oxides keeps growing on account of their peculiar engineered properties, which find applications in several fields, from architecture to bioengineering, from automotive to photovoltaic cells and photocatalytic devices, as well as to produce self-cleaning surfaces. This review intends to provide an overview of anodic oxidation treatments currently applied to form nanostructured oxide layers on titanium, with special reference to their whole range of applications. The different procedures and parameters of anodic oxidation will be described, giving information on the main oxide characteristics achievable: thickness, morphology, structure and composition. An analysis of the fields of application associated with specific oxide characteristics will be provided, in order to highlight the variety of properties that can be obtained, and the importance of tuning such properties as a function of the specific application. [ABSTRACT FROM AUTHOR]

Understanding the interaction between the nanomaterials and bioactive molecules are of current interest due to the potential application of nanomaterial in biomedical field. The structural, electronic and optical properties of newly synthesised fluorophore 2-(4-methoxynaphthalen-1-yl)-1-phenyl-1H-phenanthro[9.10-d]imidazole have been investigated in detail. The imidazole absorbs strongly on the surface of TiO nanocrystals probably because of the chemical affinity of azomethine nitrogen atom of the imidazole, resulting in lowering the HOMO and LUMO energy levels. The TEM, SEM and EDX spectra confirm the adsorption of imidazole on the surface of TiO nanocrystals. The growth behavior and stability of small stoichiometric (TiO) clusters have been analysed by using density functional theory which reveals that clusters prefers three-dimensional structures. In addition, the interaction between the ground state structure of the (TiO) cluster and a single imidazole molecule have been studied. The calculated binding energy (E) and the energy gap (E) indicate that the imidazole molecule preferably binds to the Ti atom of the (TiO) clusters through its azomethine nitrogen atom; the binding energy is in range 5.24-7.89 eV. In order to understand the binding interaction with DNA docking study has been carried out. [ABSTRACT FROM AUTHOR]

A comparative study of oxidation methods to create Cu surfaces with controlled wettability is reported. Micro/nanostructures of Cu oxides are formed on Cu substrates using different chemical and thermal oxidation methods. The morphology and wetting characteristics of the resulting surfaces are characterized using atomic force microscopy, scanning electron microscopy, X-ray diffraction, and contact angle measurements. Chemical oxidation in alkali solutions can form uniform copper oxide layers with high roughness factors without causing thermal stress problems that often hamper thermal oxidation. By combining chemical oxidation with a hydrophobic coating, a wide range of wettability control is demonstrated from superhydrophilic ( < 10°) to superhydrophobic ( > 170°). Superhydrophilic CuO layers uniformly formed on Cu powder and Cu micropost wick surfaces lead to significant improvement in the capillary and heat transfer performance compared with comparable unoxidized Cu wicks. The present work motivates further studies to exploit the benefits of nanostructured Cu surfaces in various phase change heat transfer applications. [ABSTRACT FROM PUBLISHER]

This article reviews the latest advances in the production and investigation of the properties of TiO-based nanomaterials as photocatalysts for water decomposition into molecular oxygen and hydrogen, a component of disinfecting, photooxidative, and self-cleaning surfaces, and materials for sensors and catalysts. [ABSTRACT FROM AUTHOR]

In this study, we report on the nanocrystalline powders of TiO and Fe-doped TiO (anatase and rutile phases) prepared by sol-gel method. The X-ray diffraction and Raman spectroscopy measurements indicated the presence of anatase or rutile phase in nanopowders. TEM micrographs showed 10 and 112 nm average particle sizes for anatase and rutile, respectively. Furthermore, their thermoluminescence properties were analyzed. [ABSTRACT FROM AUTHOR]

We present a novel approach to cover different substrates with thin light-sensitive layers that consist of organic-capped TiO2 nanorods (NRs). Such NR-based coatings exhibit an increasing initial hydrophobicity with increasing NR length, and they demonstrate a surface transition from this highly hydrophobic state to a highly hydrophilic one under selective UV–laser irradiation. This behaviour is reversed under long dark storage. Infrared spectroscopy measurements reveal that light-driven wettability changes are accompanied by a progressive hydroxylation of the TiO2 surface. The surfactant molecules that cover the NRs do not appear to suffer for any significant photocatalytic degradation. [ABSTRACT FROM AUTHOR]

This article aims to develop a new heat-transfer surface on which both heat-transfer enhancement and fouling prevention can be observed. One of the potential methods is to coat a thin layer on the heat-transfer surface with nanometer material. The selection of coated nanometer material, the preparation, and characterization of nanometer coatings on heat-transfer surface, including the measurement and calculation of the coated thickness, contact angle and surface free energy, the experiments on heat transfer of flow boiling and antifouling are all investigated in this article. The results declare that heat-transfer film coefficients of flow boiling on TiO2 coating surfaces with film thickness of 1.41 x 10-7 and 1.587 x 10-6 m are higher than those on uncoated surface of heated tube. The fouling resistance on the surface modified with nanometer material is lower than that on the untreated heat-transfer surface and remains constant during a long operating time. Under present experimental conditions, the coated heat-transfer surface with thin film thickness of 1.41 x 10-7 m is the best one in enhancing heat transfer of flow boiling and preventing fouling, since its surface free energy is the lowest one. [ABSTRACT FROM AUTHOR]

The development of mold films on the cement surfaces of buildings is a health and safety problem for the population, aesthetic but also in terms of their durability. The use of specific performance of cementitious composites containing TiO2 nanoparticles, photoactivated by UV radiation, can be a viable solution to mitigate to eliminate these problems. The experimental studies presented aim to analyze the capacity to inhibit the development of mold type Aspergillus and Penicillium on the surface of composite materials with nano-TiO2 content and the identification of the optimal range of nanomaterial addition. The identification and analysis of the inhibition halo (zone with a biological load of maximum 1–10 colonies of microorganisms) confirmed the biocidal capacity of the cementitious composites, but also indicated the possibility that an excess of TiO2 nanoparticles in the mixture could induce a development of cell resistance, which would be unfavorable both in terms of behavior and in terms of cost. [ABSTRACT FROM AUTHOR]

In this study, the characteristics of different types of nanosheet membranes were reviewed in order to determine which possessed the optimum propensity for antifouling during water purification. Despite the tremendous amount of attention that nanosheets have received in recent years, their use to render membranes that are resistant to fouling has seldom been investigated. This work is the first to summarize the abilities of nanosheet membranes to alleviate the effect of organic and inorganic foulants during water treatment. In contrast to other publications, single nanosheets, or in combination with other nanomaterials, were considered to be nanostructures. Herein, a broad range of materials beyond graphene-based nanomaterials is discussed. The types of nanohybrid membranes considered in the present work include conventional mixed matrix membranes, stacked membranes, and thin-film nanocomposite membranes. These membranes combine the benefits of both inorganic and organic materials, and their respective drawbacks are addressed herein. The antifouling strategies of nanohybrid membranes were divided into passive and active categories. Nanosheets were employed in order to induce fouling resistance via increased hydrophilicity and photocatalysis. The antifouling properties that are displayed by two-dimensional (2D) nanocomposite membranes also are examined. [ABSTRACT FROM AUTHOR]