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We inquire into the role of Turing's biological thought in the development of his concept of intelligent machinery. We trace the possible relations between his proto-connectionist notion of 'organising' machines in Turing (1948) on the one hand and his mathematical theory of morphogenesis in developmental biology (1952) on the other. These works were concerned with distinct fields of inquiry and followed distinct paradigms of biological theory, respectively postulating analogues of Darwinian selection in learning and mathematical laws of form in organic pattern formation. Still, these strands of Turing's work are related, first, in terms of being amenable in principle to his (1936) computational method of modelling. Second, they are connected by Turing's scattered speculations about the possible bearing of learning processes on the anatomy of the brain. We argue that these two theories form an unequal couple that, from different angles and in partial fashion, point towards cognition as a biological and embodied phenomenon while, for reasons inherent to Turing's computational approach to modelling, not being capable of directly addressing it as such. We explore ways in which these two distinct-but-related theories could be more explicitly and systematically connected, using von Neumann's contemporaneous and related work on Cellular Automata and more recent biomimetic approaches as a foil. We conclude that the nature of 'initiative' and the mode of material realisation are the key issues that decide on the possibility of intelligent machinery in Turing.
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Biología Evolutiva , Biología Evolutiva/historia , Historia del Siglo XX , Morfogénesis , Selección Genética , Inteligencia , Modelos Biológicos , Encéfalo/crecimiento & desarrollo , Encéfalo/fisiología , Encéfalo/embriología , Aprendizaje , Evolución BiológicaRESUMEN
This study introduces an innovative LED-IoT photoreactor, representing a significant advancement in response to the demand for sustainable water purification. The integration of LED-IoT installations addresses the challenge of intermittent sunlight availability, employing LEDs with a spectrum mimicking natural sunlight. Passive Infra-Red (PIR) sensors and Internet of things (IoT) technology ensure consistent radiation intensity, with the LED deactivating in ample sunlight and activating in its absence. Utilizing a visible light-absorbing photocatalyst developed through sol-gel synthesis and mild-temperature calcination, this research demonstrates a remarkable carbamazepine removal efficiency exceeding 95% under LED-IoT system illumination, compared to less than 90% efficiency with sunlight alone, within a 6-h exposure period. Moreover, the designed photocatalytic system achieves over 60% mineralization of carbamazepine after 12 h. Notably, the photocatalyst demonstrated excellent stability with no performance loss during five further cycles. Furthermore, integration with renewable energy sources facilitated continuous operation beyond daylight hours, enhancing the system's applicability in real-world water treatment scenarios. A notable application of the LED-IoT system at an operating sewage treatment plant showed nearly 80% efficiency in carbamazepine removal from sewage in the secondary settling tank after 6 h of irradiation, coupled with nearly 40% mineralization efficiency. Additionally, physicochemical analyses such as XPS and STA-FTIR confirm that the carbamazepine photooxidation process does not affect the surface of the photocatalyst, showing no adsorption for degradation products.
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Carbamazepina , Energía Solar , Contaminantes Químicos del Agua , Purificación del Agua , Carbamazepina/química , Carbamazepina/aislamiento & purificación , Purificación del Agua/métodos , Contaminantes Químicos del Agua/química , Luz Solar , Eliminación de Residuos Líquidos/métodos , CatálisisRESUMEN
This study presents a thorough spectroscopic analysis of TiO2-Pt systems under LED irradiation, with a focus on elucidating the photodeposition process of Pt nanoparticles onto TiO2 surfaces. The methodology leverages an innovative LED photoreactor tailored to a specific spectral range, enabling precise characterization of the excitation spectrum of TiO2-Pt composites. Through the identification of Pt precursor species and their excitation under LED-UV light, a photodeposition mechanism is proposed involving concurrent excitation of both the TiO2 semiconductor and the H2PtCl6 precursor. The LED photoreactors are employed to scrutinize the excitation profile of TiO2-Pt materials, revealing that the incorporation of Pt nanoparticles does not expand TiO2's absorption spectrum. Furthermore, UV-A exposure in the absence of Pt did not induce the formation of surface defects, underscoring the lack of visible light activity in TiO2-Pt systems. Spectroscopic analyses, complemented by naproxen photooxidation experiments, indicate the absence of a significant plasmonic effect in Pt nanoparticles within the experimental framework. Mass spectroscopy results corroborate the presence of distinct naproxen degradation pathways, suggesting minimal influence from photocatalyst properties. This research provides a detailed spectroscopic insight into TiO2-Pt photocatalysis, enriching the knowledge of photocatalytic materials in LED lighting.
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This investigation introduces an innovative approach to microwave-assisted crystallization of titania nanoparticles, leveraging an in situ process to expedite anatase crystallization during microwave treatment. Notably, this technique enables the attainment of crystalline material at temperatures below 100 °C. The physicochemical properties, including crystallinity, morphology, and textural properties, of the synthesized TiO2 nanomaterials show a clear dependence on the microwave crystallization temperature. The presented microwave crystallization methodology is environmentally sustainable, owing to heightened energy efficiency and remarkably brief processing durations. The synthesized TiO2 nanoparticles exhibit significant effectiveness in removing formic acid, confirming their practical utility. The highest efficiency of formic acid photodegradation was demonstrated by the T_200 material, reaching almost 100% efficiency after 30 min of irradiation. Furthermore, these materials find impactful application in dye-sensitized solar cells, illustrating a secondary avenue for the utilization of the synthesized nanomaterials. Photovoltaic characterization of assembled DSSC devices reveals that the T_100 material, synthesized at a higher temperature, exhibits the highest photoconversion efficiency attributed to its outstanding photocurrent density. This study underscores the critical importance of environmental sustainability in the realm of materials science, highlighting that through judicious management of the synthesis method, it becomes feasible to advance towards the creation of multifunctional materials.
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Detection and quantification of various organic chemicals in the environment is critical to track their fate and control their levels. 2,4-Dichlorophenoxyacetic acid (2,4-D) is a widely applied phenoxy herbicide with potential toxicity to fish and other aquatic organisms. In this study, we address the need for improved detection of 2,4-D by introducing a novel analytical method for its quantification. This method relies on the selective extraction of 2,4-D using MIPs and their subsequent direct analysis using ambient plasma mass spectrometry. During the synthesis, MIPs with various degrees of glycidol (GLY) functionalization were obtained. Experimental data showed that MIPs with no GLY functionalization displayed the highest adsorption capacity. Conversely, MIPs with 30% GLY functionalization exhibited the greatest selectivity for 2,4-D, rendering them valuable for extraction of 2,4-D even in the presence of other contaminants. Finally, the obtained MIPs were applied for quantification of 2,4-D in various water samples through direct analysis using a specially designed ambient plasma mass spectrometry setup. This approach improved the detection limits by 200-fold compared to pure solution analysis. The quantification of 2,4-D in river water samples yielded highly satisfactory recoveries, demonstrating the effective utility of the proposed analytical setup for real-life water sample analysis.
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In this study, we investigate the role of microwave technology in the fabrication of yttrium-doped TiO2 through a comparative analysis of hydrothermal techniques. Microwave-assisted hydrothermal synthesis offers advantages, but a comprehensive comparison between microwave-assisted and conventional methods is lacking. Therefore, in our investigation, we systematically evaluate and compare the morphological, structural, and optical properties of yttrium-doped TiO2 samples synthesized using both techniques. The X-ray diffraction (XRD) patterns confirm the anatase tetragonal structure of the synthesized TiO2-Y systems, while the larger ion radius of yttrium (Y3+) compared to titanium (Ti4+) presents challenges for yttrium to incorporate into the TiO2 lattice. The X-ray Photoelectron Spectroscopy (XPS) revealed a significant difference in the atomic content of yttrium between the TiO2-Y systems synthesized using microwave-assisted and conventional methods. This finding suggests that the rapid microwave method is more effective in successfully doping TiO2 with rare earth metals such as yttrium. The photo-oxidation of carbamazepine (CBZ) using TiO2-Y systems demonstrated high efficiency under UV-LED light. Microwave-synthesized TiO2-Y demonstrates improved photo-oxidation efficiency of CBZ, attributed to enhanced absorption, charge transfer, surface area, and crystallite size. Overall, the microwave-synthesized TiO2-Y systems showed promising performance for the photo-oxidation of CBZ, with improved efficiency compared to conventional synthesis methods.
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Responding to the growing concerns about environmental pollutants, scientists are increasingly turning to innovative solutions rooted in the field of environmental science. One such promising avenue combines the robustness of traditional photocatalysis with the precision of molecular imprinting, leading to the proposition of molecularly imprinted photocatalysts (MIPCs). These MIPCs hold the potential to specifically target and eliminate environmental pollutants, marking them as a promising tool in modern environmental remediation. As researchers delve deeper into this field, the design and optimization of MIPCs have become hotbeds for scientific inquiry. This comprehensive overview delves into the multifaceted approaches to MIPC design, elucidating on aspects like the selection of appropriate photocatalytic bases, the pivotal role of templates, the choice of monomeric building blocks, and the integration of effective cross-linking agents. However, as with all burgeoning technologies, the development of MIPCs is not without its challenges. These potential impediments to the successful innovation and implementation of MIPCs are also explored.
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Tetramethylalloxazines (TMeAll) have been found to have a high quantum yield of singlet oxygen generation when used as photosensitizers. Their electronic structure and transition energies (S0 â Si, S0 â Ti, T1 â Ti) were calculated using DFT and TD-DFT methods and compared to experimental absorption spectra. Generally, TMeAll display an energy diagram similar to other derivatives belonging to the alloxazine class of compounds, namely π,π* transitions are accompanied by closely located n,π* transitions. Photophysical data such as quantum yields of fluorescence, fluorescence lifetimes, and nonradiative rate constants were also studied in methanol (MeOH), acetonitrile (ACN), and 1,2-dichloroethane (DCE). The transient absorption spectra were also analyzed. To assess cytotoxicity of new compounds, a hemolytic assay was performed using human red blood cells (RBC) in vitro. Subsequently, fluorescence lifetime imaging experiments (FLIM) were performed on RBC under physiological and oxidative stress conditions alone or in the presence of TMeAll allowing for pinpointing changes caused by those compounds on the intracellular environment of these cells.
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This study focused on a direct comparison of conventional hydrothermal and microwave treatment during the synthesis of TiO2-Fe3O4 photocatalyst, which is an effective catalyst for decomposing metronidazole. The photocatalyst underwent various characterization analyses, including X-ray diffraction, Raman spectroscopy, transmission electron microscopy, energy dispersive X-ray, and diffuse reflectance spectroscopy. The Raman spectroscopy analysis revealed that the materials obtained through the conventional hydrothermal treatment consisted of separate phases of anatase and magnetite. On the other hand, the materials synthesized using the microwave process showed a noticeable shift in the Eg band (143 cm-1) and its half-width towards higher wavenumbers. This shift is likely due to the introduction of Fe ions into the TiO2 lattice. Additionally, both conventional hydrothermal and microwave synthesis routes produced TiO2-Fe3O4 systems with superparamagnetic properties, as demonstrated by SQUID magnetic measurements. The TEM analysis revealed that the materials synthesized using the microwave process exhibited higher homogeneity, with no noticeable large aggregates observed. Finally, this work proposed a convenient LED photoreactor that effectively utilized the photo-oxidative properties of TiO2-Fe3O4 photocatalysts to remove metronidazole. Combining photoactive TiO2-Fe3O4 catalysts with an energy-efficient LED reactor resulted in a low electrical energy per order (EEO).
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This paper proposes a novel LED-assisted deposition of platinum nanoparticles on the titania surface. For the first time, this process was supported by a UV-LED solution. We used two light sources with different wavelengths (λmax = 365 and 395 nm), and power (P = 1, 5, and 10 W) because the photodeposition process based on LEDs has not been defined. The TiO2-Pt material was discovered to be nano-crystalline anatase particles with nano-platinum particles deposited on the surface of titanium dioxide. Furthermore, the luminescence intensity decreased when Pt was added to TiO2, indicating that charge carrier recombination was reduced. The spectra matching of the photocatalyst and LED reactor was performed for the first time in this work. We proposed a convenient LED reactor that focused light in the range of 350-450 nm, allowing us to effectively use photo-oxidative properties of TiO2-Pt materials in the process of removing 4-chlorophenol. In the presented work, the LED light source plays a dual role. They first induce the platinum photodeposition process, before becoming an important component of tailored photoreactors, which is an important innovative aspect of this research.
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This study presents the results of research on cement mortars amended with two zinc oxides obtained by two different methods: hydrothermal ZnO-H and microwave ZnO-M. Our work indicates that, in contrast to spherical ZnO-H, ZnO-M was characterized by a columnar particle habit with a BET surface area of 8 m2/g, which was four times higher than that obtained for hydrothermally obtained zinc oxide. In addition, ZnO-M induced much better antimicrobial resistance, which was also reported in cement mortar with this oxide. Both zinc oxides showed very good photocatalytic properties, as demonstrated by the 4-chlorophenol degradation test. The reaction efficiency was high, reaching the level of 90%. However, zinc oxides significantly delayed the cement binder setting: ZnO-H by 430 min and ZnO-M by 380 min. This in turn affected the increments in compressive strength of the produced mortars. No significant change in compressive strength was observed on the first day of setting, while significant changes in the strengths of mortars with both zinc oxides were observed later after 7 and 28 days of hardening. As of these times, the compressive strengths were about 13-15.5% and 12-13% higher than the corresponding values for the reference mortar, respectively, for ZnO-H and ZnO-M. There were no significant changes in plasticity and flexural strength of mortars amended with both zinc oxides.
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The main goal of the study was the hydrothermal-assisted synthesis of TiO2-ZnO systems and their subsequent use in photoactive processes. Additionally, an important objective was to propose a method for synthesizing TiO2-ZnO systems enabling the control of crystallinity and morphology through epitaxial growth of ZnO nanowires. Based on the results of X-ray diffraction analysis, in the case of materials containing a small addition of ZnO (≥5 wt.%), no crystalline phase of wurtzite was observed, proving that a high amount of modified titanium dioxide can inhibit the crystallization of ZnO. The transmission electron microscopy (TEM) results confirmed the formation of ZnO nanowires for systems containing ≥ 5% ZnO. Moreover, for the synthesized systems, there were no significant changes in the band gap energy. One of the primary purposes of this study was to test the TiO2-ZnO system in the photodegradation process of 4-chlorophenol using low-power UV-LED lamps. The results of photo-oxidation studies showed that the obtained binary systems exhibit good photodegradation and mineralization efficiency. Additionally, it was also pointed out that the dye-sensitized solar cells can be a second application for the synthesized TiO2-ZnO binary systems.
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Within this study, the ZrO2/lignin and ZrO2-SiO2/lignin hybrid materials were obtained for the first time. The mechanical grinding method was used for this purpose. In order to determine the properties of obtained lignin-based hybrids and the components used to produce them, as well as to evaluate the efficiency of their preparation, the authors used such research techniques as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), elemental analysis, porous structure analysis and thermal stability assessment (TGA/DTG). The next step involved using the components and produced hybrid materials as polymer fillers for poly(methyl methacrylate) (PMMA). The obtained lignin-based hybrid biocomposites have then been thoroughly characterized using gel permeation chromatography (GPC), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and hardness testing. All the conducted tests confirm the possibility of using the obtained bio-based products in practice, within the widely understood construction industry, for producing durable building facades or noise barriers, among others.
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Materiales Biocompatibles/química , Lignina/química , Polímeros/química , Rastreo Diferencial de Calorimetría , Fenómenos Químicos , Elementos Químicos , Dureza , Lignina/ultraestructura , Tamaño de la Partícula , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , TermogravimetríaRESUMEN
This study concerns the synthesis of biocomposites with kraft lignin, investigation of their physicochemical properties, and tests of their resistance to environmental factors such as UV irradiation and water. The biocomposites were synthesized using bisphenol A glycerolate (1 glycerol/phenol) diacrylate (BPA.DA) as a main monomer, ethylene glycol dimethacrylate (EGDMA) as a reactive diluent, and kraft lignin (L) as an environmentally friendly filler, in a UV curing process. Morphological analysis of the resulting materials was carried out using scanning electron microscopy and confocal microscopy. Thermal properties were investigated using thermogravimetric analysis. Tensile and flexural tests were performed for all obtained materials. Additionally, the wettability and swelling of the obtained composite samples were analyzed. The changes observed in the structure and properties of the polymers as a result of aging were investigated by means of ATR-FTIR analysis, optical profilometry and hardness tests. The results obtained regarding the effect of lignin addition on the properties of composite materials, with particular emphasis on their resistance to environmental factors, may be of crucial importance for their further applications, inter alia as UV-curable coating materials.
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Lignina/química , Ensayo de Materiales , Metacrilatos/químicaRESUMEN
The TiO2-Fe3O4 composite materials were fabricated via the hydrothermal-assisted technique. It was determined how the molar ratio of TiO2 to Fe3O4 influences the crystalline structure and morphology of the synthesized composite materials. The effect of the molar ratio of components on the antibacterial activity was also analyzed. On the basis of XRD patterns for the obtained titanium(IV) oxide-iron(II, III) oxide composites, the two separate crystalline forms-anatase and magnetite -were observed. Transmission electron microscopy revealed particles of cubic and tetragonal shape for TiO2 and spherical for Fe3O4. The results of low-temperature nitrogen sorption analysis indicated that an increase in the iron(II, III) oxide content leads to a decrease in the BET surface area. Moreover, the superparamagnetic properties of titanium(IV) oxide-iron(II, III) oxide composites should be noted. An important aim of the work was to determine the antibacterial activity of selected TiO2-Fe3O4 materials. For this purpose, two representative strains of bacteria, the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, were used. The titanium(IV) oxide-iron(II, III) oxide composites demonstrated a large zone of growth inhibition for both Gram-positive and Gram-negative bacteria. Moreover, it was found that the analyzed materials can be reused as antibacterial agents in three consecutive cycles with good results.
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Starch is a modern and prospective biodegradable material, which could improve lithium-ion batteries by making them safer and thus increasing the energy density and capacity of the cells. The main aim of this study was to research the influence of the physical and chemical properties of different botanical origin starches on their electrochemical properties. The investigation was carried out by examining the colloid stability of starches in water solution at room temperature, and the size of particles, which gave really good stability results. Moreover, the vibrations and the functional groups structure were described by Fourier Transform Infrared Spectroscopy (FTIR). The surface properties were characterized by determining the specific surface area, pore diameter and volume diameter. The structures of the granules were determined by scanning electron microscope (SEM) measurement. The results of the electrochemical investigations showed good cyclic reversibility and stability. The research was aimed at improving and modifying current lithium-ion cells using biodegradable material as an active anode material, which is connected with the currently well-known "Green Chemistry".
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Técnicas Electroquímicas/métodos , Electrodos , Almidón/química , Espectroscopía Dieléctrica , Impedancia Eléctrica , Tecnología Química Verde , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Hydrothermal crystallization was used to synthesize an advanced hybrid system containing titania and molybdenum disulfide (with a TiO2:MoS2 molar ratio of 1:1). The way in which the conditions of hydrothermal treatment (180 and 200 °C) and thermal treatment (500 °C) affect the physicochemical properties of the products was determined. A physicochemical analysis of the fabricated materials included the determination of the microstructure and morphology (scanning and transmission electron microscopy-SEM and TEM), crystalline structure (X-ray diffraction method-XRD), chemical surface composition (energy dispersive X-ray spectroscopy-EDS) and parameters of the porous structure (low-temperature N2 sorption), as well as the chemical surface concentration (X-ray photoelectron spectroscop-XPS). It is well known that lithium-ion batteries (LIBs) represent a renewable energy source and a type of energy storage device. The increased demand for energy means that new materials with higher energy and power densities continue to be the subject of investigation. The objective of this research was to obtain a new electrode (anode) component characterized by high work efficiency and good electrochemical properties. The synthesized TiO2-MoS2 material exhibited much better electrochemical stability than pure MoS2 (commercial), but with a specific capacity ca. 630 mAh/g at a current density of 100 mA/g.
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The presented study describes the application of lignin-based dual component fillers into low-density polyethylene (LDPE) and an examination of their selected properties. The main experimental procedure was focused on the preparation of thin sheet films using polyethylene and its composites with 5% by wt. of fillers: MgO, MgO-lignin dual phase systems with varying amounts of lignin and pristine lignin. Analysis of morphology revealed that elongated voids appeared in the structure for hybrid filler with a higher content of lignin (min. 50% by wt. of lignin versus MgO) and also for pristine lignin. Moreover, the prepared sheets were subjected to the thermoforming process by using the positive forming method (male mold). The thermoforming ability of all composites was evaluated by means of a comparison of wall thickness distribution on thermoformed shapes. The most noticeable percentage of wall thinning occurred for films which consisted of LDPE/MgO-lignin (5:1 wt./wt.) composite. In contrast, the best material arrangement and the highest mean percentage wall thickness were observed in the case of the shape formed with LDPE/MgO-lignin (1:5 wt./wt.). In addition, as part of research studies, the measurements of the contact angle have been conducted. The analysed LDPE films, in particular LDPE/MgO-L, have been recognized as materials with high wettability.
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Binary oxide systems containing TiO2 and CuO were synthesized using hydrothermal treatment and shown to have enhanced antibacterial properties. A detailed investigation was made of the effect of the molar ratio of components (TiO2:CuOâ¯=â¯7:3, 5:5, 3:7, 1:9) on the physicochemical parameters and antibacterial activity. Analysis of morphology (SEM, TEM and HRTEM) confirmed the presence of spherical and sheet-shaped particles. On the XRD patterns for the binary oxide materials, two crystalline forms (anatase and monoclinic CuO) were observed. It was found that an increase in CuO content led to a decrease in the BET surface area of the TiO2-CuO binary oxide systems. The synthesized TiO2-CuO materials exhibited very good antibacterial activity against both Gram-positive (methicillin-resistant Staphylococcus aureus and Bacillus cereus) and Gram-negative (Salmonella Enteritidis and Pseudomonas aeruginosa) bacteria. The obtained results show that TiO2-CuO oxide materials may have applications in the biomedical and food industries.
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Antibacterianos/farmacología , Cobre/farmacología , Temperatura , Titanio/farmacología , Agua/química , Adsorción , Bacterias/efectos de los fármacos , Cristalización , Pruebas de Sensibilidad Microbiana , Nitrógeno/química , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Difracción de Rayos XRESUMEN
Titania has properties that enable it to be used in a variety of applications, including self-cleaning surfaces, air and water purification systems, hydrogen evolution, and photoelectrochemical conversion. In order to improve the properties of titanium dioxide, modifications are made to obtain oxide/hybrid systems that are intended to have the properties of both components. In particular, zinc oxide, zirconia and molybdenum disulfide have been proposed as the second component of binary systems due to their antibacterial, electrochemical and photocatalytic properties. This paper presents a review of the current state of knowledge on the synthesis and practical utility of TiO2-ZnO and TiO2-ZrO2 oxide systems and TiO2-MoS2 hybrid materials. The first part focuses on the hydrothermal method; then a review is made of the literature on the synthesis of the aforementioned materials using the sol-gel method. In the last section, the literature on the electrospinning method of synthesis is reviewed. The most significant physico-chemical, structural and dispersive-morphological properties of binary hybrid systems based on TiO2 are described. A key aim of this review is to indicate the properties of TiO2-ZnO, TiO2-ZrO2 and TiO2-MoS2 hybrid systems that have the greatest importance for practical applications. The variety of utilities of titania-based hybrid materials is emphasized.