The characteristics of dopamine self-polymerization were used to cover the nano-titanium dioxide (TiO2) surface and produce nano-titanium dioxide-polydopamine (TiO2-PDA). The reducing nature of dopamine was then used to reduce silver nitrate to silver elemental particles on the modified nano-titanium dioxide: The resulting TiO2-PDA-Ag nanoparticles were used as antimicrobial agents. Finally, the antibacterial agent was mixed with silicone to obtain an antibacterial silicone composite material. The composition and structure of antibacterial agents were analyzed by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron energy spectroscopy, and X-ray diffraction. Microscopy and the antibacterial properties of the silicone antibacterial composites were studied as well. The TiO2-PDA-Ag antimicrobial agent had good dispersion versus nano-TiO2. The three were strongly combined with obvious characteristic peaks. The antibacterial agents were evenly dispersed in silicone, and the silicone composite has excellent antibacterial properties. Bacillus subtilis (B. subtilis) adhesion was reduced from 246 × 104 cfu/cm2 to 2 × 104 cfu/cm2, and colibacillus (E. coli) reduced from 228 × 104 cfu/cm2 leading to bacteria-free adhesion.

Titanium dioxide was synthesized via hydrolysis of titanium (IV) isopropoxide using a sol-gel method, under neutral or basic conditions, and heated in the microwave-assisted solvothermal reactor and/or high-temperature furnace. The phase composition of the prepared samples was determined using the X-ray diffraction method. The specific surface area and pore volumes were determined through low-temperature nitrogen adsorption/desorption studies. The photoactivity of the samples was tested through photocatalytic reduction of carbon dioxide. The composition of the gas phase was analyzed using gas chromatography, and hydrogen, carbon oxide, and methane were identified. The influence of pH and heat treatment on the physicochemical properties of titania-based materials during photoreduction of carbon dioxide have been studied. It was found that the photocatalysts prepared in neutral environment were shown to result in a higher content of hydrogen, carbon monoxide, and methane in the gas phase compared to photocatalysts obtained under basic conditions. The highest amounts of hydrogen were detected in the processes using photocatalysts heated in the microwave reactor, and double-heated photocatalysts.

To investigate the carcinogenicity of anatase-type nano-titanium dioxide (aNTiO2), F344/DuCrlCrlj rats were exposed to aNTiO2 aerosol at concentrations of 0, 0.5, 2, and 8 mg/m3. The rats were divided into 2 groups: carcinogenicity study groups were exposed for two years, and satellite study groups were exposed for one year followed by recovery for 1 day, 26 weeks, and 52 weeks after the end of exposure. In the carcinogenicity groups, bronchiolo-alveolar carcinomas were observed in two 8 mg/m3-exposed males, showing an increasing trend by Peto\'s test. However, this incidence was at the upper limit of JBRC\'s historical control data. Bronchiolo-alveolar adenomas were observed in 1, 2, 3, and 4 rats of the 0, 0.5, 2, and 8 mg/m3-exposed females and were not statistically significant. However, the incidence in the 8 mg/m3-exposed females exceeded JBRC\'s historical control data. Therefore, we conclude there is equivocal evidence for the carcinogenicity of aNTiO2 in rats. No lung tumors were observed in the satellite groups. Particle-induced non-neoplastic lesions (alveolar epithelial hyperplasia and focal fibrosis) were observed in exposed males and females in both the carcinogenicity and satellite groups. Increased lung weight and neutrophils of bronchoalveolar lavage fluid were observed in the 8 mg/m3-exposed carcinogenicity groups. The aNTiO2 deposited in the lungs of the satellite group rats was decreased at 26 weeks after the end of exposure compared to 1 day after the end of exposure. At 52 weeks after the end of exposure, the decreased level was the same at 26 weeks after the end of exposure.

Graffiti on construction materials has significant social and economic impacts, especially on artistic and historical artefacts. Anti-graffiti protective coatings are used to generate low surface energies that limit graffiti adhesion to the surface, thereby reducing surface damage and facilitating removal. The anti-graffiti properties of three commercial TiO2-based coatings were tested under outdoor exposure conditions using four colours of graffiti paint (red, blue, black, and white). Chemical removers were used to clean the stained surfaces to understand the impact of the photocatalytic coatings during the conventional cleaning procedure. The effectiveness of cleaning was assessed by visual observations, colour measurements, and the percentage of residual stain. The anti-graffiti efficacy was strongly dependent on the colour of the graffiti and characteristics of the TiO2 coating. The cleaning performance of TiO2-treated samples was likely related to the photocatalytic redox reactions that decompose the graffiti. Additionally, their hydrophilicity may also prevent the adhesion and/or penetration of graffiti paint on the surface and/or pore matrix.

Glass ionomer cements (GICs) are the common materials employed in pediatric dentistry because of their specific applications in class I restorations and atraumatic restoration treatments (ART) of deciduous teeth in populations at high risk of caries. Studies show a limited clinical durability of these materials. Attempts have thus been made to incorporate nanoparticles (NPs) into the glass ionomer for improving resistance and make it like the tooth structure. An in vitro experimental study was conducted using the required samples dimensions and prepared based on the test being carried out on the three groups with or without the modification of light-cured glass ionomer. Samples were grouped as follows: control group (G1_C), 2% silver phosphate/hydroxyapatite NPs group (G2_SPH), and 2% titanium dioxide NPs group (G3_TiO2). The physical tests regarding flexural strength (n = 10 per group), solubility (n = 10 per group), and radiopacity (n = 3 per group) were performed. The data were analyzed by Shapiro Wilks test, and one-way analysis of variance (one-way ANOVA), and multiple comparisons by post hoc Tukey\'s test. The p-value of < 0.05 was considered significant. No statistically significant difference was observed between the control group (G1_C) and (G2_SPH) (p = 0.704) in the flexural strength test, however differences were found between G2_SPH and G3_TiO2 groups, ANOVA (p = 0.006); post hoc Tukey\'s test (p = 0.014). Pertaining to the solubility, G2_SPH obtained the lowest among the three groups, ANOVA (p = 0.010); post hoc Tukey\'s test (p = 0.009). The three study groups obtained an adequate radiopacity of >1 mm Al, respectively. The resin-modified glass ionomer cement (RMGIC) was further modified with 2% silver phosphate/hydroxyapatite NPs to improve the physical properties such as enhancing the solubility and sorption without compromising the flexural strength and radiopacity behavior of modified RMGIC. The incorporation of 2% titanium dioxide NPs did not improve the properties studied.

Nanotechnology has been established as a promising alternative for treating a myriad of disease-causing microorganisms that pose threats to human health. The utilization of nanoparticles (NPs) emerges as a strategy to enhance the therapeutic arsenal against these diseases, especially given the tendency of many pathogens to develop resistance to conventional medications. Notably, titanium dioxide nanoparticles (TiO2NPs) have garnered attention for their multifaceted biomedical applications, encompassing antibacterial, antifungal, antiviral, anticancer, antioxidant, and drug delivery properties. This review focuses on the cutting-edge potential of TiO2NPs against helminths, protozoa, and vectors, underscoring their pivotal role in combating these health-threatening agents.

Aquatic selenium (Se) oxyanions have profound ecosystem and human health impacts, necessitating their conversion and immobilization into elemental Se(0) to mitigate the aquatic Se pollution. While thermodynamically favorable, this transformation encounters kinetic limitations, especially for selenate (SeO42-) or Se(VI). To lower the activation barrier, we investigated the electrocatalytic Se(VI) transformation using five affordable catalysts on graphite cathodes, including TiO2, underpotentially deposited Cu (UPD Cu), underpotentially deposited Cd (UPD Cd), Co, and CuFe. Among these five catalysts, we identified characteristic Se(VI) reduction peaks for TiO2 through cyclic voltammetry. Other catalysts removed less than 5% of 1-mM Se(VI) in 24-h chronoamperometry tests while leaching ppm-level metal cations in the treated water. In contrast, TiO2 as the electrocatalyst could remove more than 80% of 1-mM Se(VI) with negligible catalyst dissolution. Mechanistic investigations revealed a six-electron Se(VI)/Se(0) reduction pathway at -0.30 V (vs. Ag/AgCl), resulting in red Se(0) deposits on the TiO2-coated graphite cathode. Further potential decrease to more negative than -0.45 V led to Se(-II) formation, triggering cathodic Se(0) dissolution and surface regeneration. Electrochemical impedance spectroscopy indicated that Se(VI) reduction was optimal with a moderate TiO2 loading of 0.55 mg cm-2 and acidic environments (pH=1.0∼2.5), achieving an optimized removal of 88.7 ± 2.3% under -0.70 V and an energy input of 3.6 kWh kg-1 Se. These findings lay the foundation for efficient selenate removal from impaired waters. Future efforts should evaluate catalyst performance over time and refine electrode and reactor designs to improve efficiency.

Our previous studies have shown physiological and yield intensification of selected crops with the application of nanoparticles (NPs). However, the impact on the quantitative, qualitative, and yield parameters of maize (Zea mays L.) in field conditions remains highly debated. This study aimed to evaluate the effects of zinc oxide (ZnO-NPs), gold NPs anchored to meso-biosilica (Au-NP-bioSi), and titanium dioxide (TiO2-NPs) as biological stimulants under field conditions during the vegetation season of 2021 in the Central European region. The study assessed the effects on the number of plants, yield, yield components, and nutritional quality, including mineral nutrients, starch, and crude protein levels. The potential translocation of these chemically-physically stable NPs, which could pose a hazard, was also investigated. The results indicate that Au-NP-bioSi and ZnO-NPs-treatments were the most beneficial for yield and yield components at a statistically significant level. Mineral nutrient outcomes were varied, with the NP-free variant performing the best for phosphorus-levels, while Au-NP-bioSi and ZnO-NPs were optimal for crude protein. Starch content was comparable across the TiO2-NPs, Au-NP-bioSi, and control variants. Importantly, we observed no hazardous translocation of NPs or negative impacts on maize grain quality. This supports the hypothesis that NPs can serve as an effective tool for precise and sustainable agriculture.

Perovskite solar cells (PSCs), which are constructed using organic-inorganic combination resources, represent an upcoming technology that offers a competitor to silicon-based solar cells. Electron transport materials (ETMs), which are essential to PSCs, are attracting a lot of interest. In this section, we begin by discussing the development of the PSC framework, which would form the foundation for the requirements of the ETM. Because of their exceptional electronic characteristics and low manufacturing costs, perovskite solar cells (PSCs) have emerged as a promising proposal for future generations of thin-film solar energy. However, PSCs with a compact layer (CL) exhibit subpar long-term reliability and efficacy. The quality of the substrate beneath a layer of perovskite has a major impact on how quickly it grows. Therefore, there has been interest in substrate modification using electron transfer layers to create very stable and efficient PSCs. This paper examines the systemic alteration of electron transport layers (ETLs) based on electron transfer layers that are employed in PSCs. Also covered are the functions of ETLs in the creation of reliable and efficient PSCs. Achieving larger-sized particles, greater crystallization, and a more homogenous morphology within perovskite films, all of which are correlated with a more stable PSC performance, will be guided by this review when they are developed further. To increase PSCs\' sustainability and enable them to produce clean energy at levels previously unheard of, the difficulties and potential paths for future research with compact ETLs are also discussed.

Titanium dioxide (TiO2) thin films prepared by the sol-gel technique have been shown to be optically isotropic and, unlike the films obtained by competitive methods, do not exhibit measurable birefringence. A series of submicrometer-thin titanium dioxide films were prepared using the sol-gel technique and then thermally annealed at different temperatures. The samples were analyzed by spectroscopic ellipsometry using the Mueller matrix formalism, X-ray diffractometry and scanning electron microscopy. The conversion of amorphous titanium dioxide to polycrystalline anatase occurred at 400 °C or higher. Crystallites of a few percent of the film thickness were observed. Nevertheless, the crystallization process did not trigger the appearance of birefringence. These observations demonstrate that high-quality planar optical waveguides can be successfully fabricated on flexible substrates, in particular those composed of efficient polymers that can withstand the aforementioned temperatures.