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The cellulose-based textiles currently used in hospitals are good conducive materials for cross-infection or transmission of diseases caused by microorganisms. Thus, great interest has been recently found in the antibacterial finishing of fabrics for practical applications to prevent the infection incidence. In this work, we developed novel SnO2/ZnO/chitosan bionanocomposites by one-step simultaneous sonochemical/sol–gel deposition to prepare an antibacterial textile as a model for combating bacterial infections. The different prepared samples were characterized using transmission electron microscope, X-ray diffraction, and scanning electron microscopy (SEM) indicating the embedded SnO2 and ZnO nanoparticles in treated fabrics. The treated fabrics were used to evaluate antibacterial activities against Escherichia coli and Streptococcus aureus as a model for Gram-negative and Gram-positive bacteria, respectively, using disk diffusion method in dark conditions as an in vitro model for treatment of bacterial wound infection. The procedure was more developed in terms of SnO2/ZnO molar ratio and using chitosan and citric acid to improve the antibacterial properties of the fabrics and their wash durability, respectively. The highest antibacterial activity of the fabrics was attained in a 50 min sonochemical coating process using SnO2/ZnO 1:2 molar ratio in initial sol and simultaneously deposited chitosan and citric acid. The presence of chitosan as complexing agent, citric acid as crosslink agent, and SnO2–ZnO heterojunction as important influencing parameters synergistically enhanced both the antimicrobial efficiency and maintenance of modified cotton durability after performing several washing cycles.

Sol–gel dip coating method has been employed for the deposition of nanostructured single nickel oxide (NiO) and zinc oxide (ZnO) films and multilayered NiO/ZnO/NiO and ZnO/NiO/ZnO films. The structural, morphology and optical properties of prepared films were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis spectroscopy, respectively. XRD analysis showed that ZnO-based films crystallized in write phase and presented an epitaxial orientation depending on the substrate. SEM images also showed uniform size distribution around 30–70 nm for all samples. Antibacterial effectiveness of NiO and ZnO- based films were tested against general Escherichia coli (E. coli ATCC 25922) and Streptococcus aureus (S. aureus, ATCC 29213) as Gram negative and Gram positive model, respectively, using the so-called drop-test method under UV light illumination and dark conditions. ZnO/NiO/ZnO film was found to be the most toxic among tested samples, followed by ZnO, NiO/ZnO/NiO and NiO films. Samples exposure to UV light resulted in higher activity compared to dark conditions against both E. coli and S. aureus, but considerably more effective in the former case. The obtained results were discussed according to the lattice matching between the heteroepitaxial films and structural modification as key roles on the preferential growth orientation and antibacterial activity.

Nickel oxide films were deposited onto glass substrates by sol–gel dip coating method using solvents of different polarities without any catalysts, templates or surfactants. Methanol, 1,4-butanediol, ethanol, and 2-propanol were used as solvents. The structural, optical and electrical properties of NiO films were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible spectroscopy and Hall effect measurements, respectively. Nickel oxide thin films with cubic phase crystal structure of various preferred orientations were obtained in the different solvents. The XRD results showed that films deposited from solution using higher polar solvents develop a (1 1 1) preferred orientation, while the (2 0 0)-orientated films were obtained using lower polar solvents. The average particle size increases with viscosity of solvents. Surface morphology of the nickel oxide film consisted of nanoparticles with uniform coverage of the substrate surface. The solvent of higher viscosity induced larger particle size. Band gap narrowing from 4.42 to 3.87 eV was observed using different solvents. The lower resistivity and Hall coefficient was obtained for prepared NiO films using higher polar solvents. The relationships between solvent physicochemical properties, preferred orientation, structural, optical and electrical properties of NiO films were investigated.

SiO 2 doped samples with different cobalt loading and pure SiO 2 and Co 3 O 4 nanopowders were synthesized by the solvothermal method and their antibacterial activities were studied. The morphology and crystallinity of the powders were analyzed by scanning electron microscopy and X-ray diffractometry patterns, respectively. The increase of particle size with doping concentration was obtained for cobalt-doped samples. The optical properties were studied using UV–vis spectroscopy. Optical studies showed a blue shift in the absorbance spectrum with increasing the doping concentration. The antibacterial activities of undoped SiO 2 , Co-doped SiO 2 and pure Co 3 O 4 nanoparticles against a Gram-negative bacterium Escherichia coli ( E. coli , ATCC 25922) and a Gram-positive bacterium Staphylococcus aureus ( S. aureus , ATCC 29213) were investigated under UV illumination and in the dark condition. Bactericidal effects were determined by the minimum inhibitory concentration (MIC) method. There was no activity for pure SiO 2 and Co 3 O 4 , however, cobalt doping significantly improved antibacterial activity against both bacteria. Bacterial growth inhibition was observed under dark condition with lower efficiency than under UV illumination. The antibacterial efficiencies were affected by the physiological status of the bacterial cells, different morphologies, particle sizes and optical properties of samples.

SnO 2 hierarchical architectures were synthesized by a surfactant-free hydrothermal synthesis route. The influence of hydrothermal temperature and treatment time on the final morphology of the nanomaterials was studied. The as-synthesized nanoparticles were characterized by X-ray powder diffraction (XRD), UV–vis spectroscopy, scanning electron microscopy (SEM) and adsorption isotherm measurement. Degradation of aniline, 4-nitroaniline and 2,4-dinitroaniline as model organic pollutants was studied in the presence and absence of ultraviolet radiation. The effects of experimental parameters including irradiation time, solution pH and organics structure on the degradability were studied. The photodegradation of the pollutants followed first-order kinetics. The influence of SnO 2 morphology on its photocatalytic activity was comparatively investigated. The SnO 2 flower-shaped catalysts showed higher activity compared with others suggesting that the morphology of the catalysts exerts a noticeable influence on their performances.

Nanostructure single ZnO, SnO2, In2O3 and composite ZnO/SnO2, ZnO/In2O3 and ZnO/SnO2/In2O3 films were prepared using sol–gel method. The obtained composite films were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV–Vis spectroscopy. The photocatalytic activities of composite films were investigated using phenol (P), 2,4-dichlorophenol (2,4-DCP), 4-chlorophenol (4-CP) and 4-aminophenol (4-AP) as a model organic compounds under UV light irradiation. Hybrid semiconductor thin films showed a higher photocatalytic activity than single component ZnO, SnO2 and In2O3 films. The substituted phenols degrade faster than phenol. The ease of degradation of phenols is different for each catalyst and the order of catalytic efficiency is also different for each phenol. The use of multiple components offered a higher control of their properties by varying the composition of the materials and related parameters such as morphology and interface. It was also found that the photocatalytic degradation of phenolic compounds on the composite films and single films followed pseudo-first order kinetics.

The nano-sized coupled oxides ZnO/SnO2 thin films in a molar ratio of 2:1 (Z2S), 1:1 (ZS) and 1:2 (ZS2) were prepared using sol–gel dip coating method and characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis spectroscopy. Escherichia coli (E. coli, ATCC 25922) was selected as a model for the Gram-negative bacteria to evaluate antibacterial property of composite samples compared with single ZnO (Z) and single SnO2 (S) films. The antibacterial activity has been studied applying the so-called antibacterial drop test under UV illumination. The bactericidal activity was estimated by relative number of bacteria survived calculated from the number of viable cells which form colonies on the nutrient agar plates. The influence of the SnO2–ZnO nanocomposite composition on the structural features and on the antibacterial properties of the thin films are reported and discussed. It is found that all coatings exhibited a high antibacterial activity. The coupled oxide photocatalyst Z2S has better photocatalytic activity to bacteria inactivation than ZS, ZS2, Z and S films. Furthermore, nanostructured films were active even in the absence of irradiation.

Indium oxide (In 2 O 3 ), zinc oxide (ZnO), stannic oxide (SnO 2 ), and titanium dioxide (TiO 2 ) thin films were prepared on glass substrates using electron beam evaporation. The samples characterized by UV–vis spectroscopy, diffraction ray-X and scanning electron microscopy techniques. The photocatalytic degradation of methylene blue in an aqueous solution, as a model compound, was investigated using different metal oxides in an attempt to compare the decomposition reaction rate. The progress of degradation was monitored using UV–vis spectrophotometry. The effects of various experimental parameters such as initial concentration of methylene blue (5–10 mg/l), pH of the solution (2–8), annealing temperature (250–550 °C), and catalyst nature and its microstructure were systematically studied in order to achieve maximum degradation efficiency. The results obtained were fitted with the Langmuir–Hinshelwood model to study the degradation kinetics and discussed in detail. Nearly complete degradation was obtained at optimal operational parameters including the higher annealing temperature of thin film and the increase in MB solution pH. The degradation with In 2 O 3 was more efficient than with SnO 2 , ZnO and TiO 2 films.