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Intensive use of antibiotics induced adaptations in bacteria, which developed antibiotic resistance. This is becoming a serious health problem, particularly in the hospital, food industry, or public transport. It is also important to produce surfaces that not only are bactericidal but also prevent adhesion and the consequent biofilm formation, which can make the bacteria resistant to conventional disinfection methods. In this work, a simple and inexpensive method to obtain surfaces TiO2 film coated has been realized to prevent attachment and bacterial proliferation on surfaces. The synthesis and deposition procedure has been finalized to the realization of a uniform coating, whose physical, morphological, and structural features are suitable to inhibit the proliferation of the bacteria and in particular the adhesion of the biofilm. The suitability of the obtained coating has been attested by RBS, X‐ray diffraction (XRD), SEM, UV‐vis, and Raman techniques. The obtained coatings were homogeneous anatase titania films with an excellent adherence to the substrate and a transmittivity higher than 80% in the visible region. The results show that the TiO2 films considerably reduce microbial contamination on the surface (~98% reduction) feature that makes this coating suitable for antibacterial applications.

In this paper we describe the effect of calcination temperature on the structural, morphological, optical and photocatalytic properties of TiO 2 nanoparticles. The titanium dioxide powders were produced by the sol-gel method starting from titanium tetraisopropoxide (TTIP) in neutral aqueous medium (pH 5.5). After that, the TiO 2 nanoparticles were treated at three different calcination temperatures for 4 h: 100, 450 and 800 °C. Then, the powders were characterized by XRD, Raman and photoluminescence techniques. We observed the anatase phase for the powders treated at 100 and 450 °C and rutile for that treated at 800 °C. The photocatalytic activity of the TiO 2 powders was investigated using Methylene Blue test and showed a strong correlation with the temperature (i.e. TiO 2 phase). The better photocatalysis exhibited by the nanoparticles treated at 100 and 450 °C compared to the powder at 800 °C was due to the higher recombination of photo-generated electrons and holes of rutile with respect to anatase. Graphic abstract

In recent years, the exploitation of natural resources and industrial development have led to the production of harmful pollutants. Much of these contaminants end up in water resources, reducing the availability of drinking water. Therefore, it is necessary to find remedies to this situation. Solutions could be the adsorption or the degradation through photocatalysis of these compounds. A good candidate for this task is titanium dioxide (TiO2), due to its non-toxicity, stability and low cost. In this work, we propose a novel synthesis of TiO2 nanoparticles (NPs), with high adsorption capacity, produced at low temperature in alkaline environment. Adsorption tests were conducted using methylene blue and diclofenac as model pollutants. Moreover, the obtained NPs have been characterized through Raman spectroscopy, Scanning and Transmission electron microscopies and with thermogravimetric analysis. The results showed a porous structure with a high surface area, able to efficiently adsorb large amounts of dye from the aqueous solution. These properties make the obtained TiO2 powders suitable for applications devoted to the adsorption and recovery of harmful compounds. Graphic abstract