Fabrication of multifunctional wool textile using the synthesis of silver-modified N-doped ZnO/TiO2 photocatalysts.

Photocatalysts and noble metals have attracted considerable attention for their potential in addressing global environmental pollution through photochemical processes. At low temperatures, multifunctional self-cleanable wool fabric was developed through green photo-sonosynthesis of N-Ag/TiO2/ZnO. A narrower bandgap of the hybrid photocatalyst, the surface plasmonic resonance effect of silver nanostructures, and nitrogen doping resulted in synergistically enhanced self-cleaning activity. The self-cleaning activity was evaluated by monitoring the discoloration of methylene blue stains on the wool fabric exposed to natural sunlight, using CIELAB color space and ΔE measurements. The ΔE value of the N-Ag/TiO2/ZnO-sonicated wool was superior, showing a value of 45.9 compared to 15.7 for the control and 28.7 for the sample coated by the stirrer. Furthermore, the nanocomposite construction improved tensile strength, enhanced fabric hydrophilicity, and reduced the yellowness index. Additionally, the synthesis of TiO2 and silver particles on ZnO particles increased surface resistance to acid, reducing ZnO acid solubility. The reflectance of the non-treated wool ranged from 5 to 20 % within 200-380 nm, while the reflectance of the Ag/TiO2/ZnO-sonicated sample remained constant at 4 %, exhibiting protection against UV rays. AATCC test revealed 100 % bacteria reduction against E. coli and S. aureus and 99 % against C. albicans fungus for N-Ag/TiO2/ZnO-sonicated sample. Moreover, cell culture assays demonstrated a viability of over 70 %, indicating non-cytotoxicity.

Facile synthesis of TiO2@ZnO nanoparticles for enhanced removal of methyl orange and indigo carmine dyes: Adsorption, kinetics.

Water pollution represents one of the most important problems affecting the health of living organisms, so it was necessary to work on the formation of active materials to get rid of pollutants. In this study, Titanium dioxide (TiO2) doping Zinc oxide (ZnO) nanocomposites were produced via simple sonication method at 500 Hz in ethanol medium. At different weight concentrations (2.5, 5, 7.5, and 10 %). The morphology, structure configuration, chemical bonding, crystalline phase, and surface properties of obtained nanocomposites were characterized via FESEM, BET, XRD, XPS, RAMAN and FTIR instrumentation. The nanocomposites were employed as an adsorbent to eliminate the methyl orange (MO) and Indigo Carmine (IC) dyes from an aqueous solution. Batch removal experiments revealed that the elimination of MO and IC dyes by the TiZnO surface was pH and doping Ti concentration-dependent, with maximum removal occurring at pH = 7 for MO and pH = 3 for IC contaminants at 10 % doping Ti concentration (Ti (10 %)@ZnO). Langmuir model fit the absorptive removal of MO and IC dyes into the Ti (10 %)@ZnO surface well. The maximal removal capacity of Ti (10 %)@ZnO nanocomposite was found to be 994.24 mg. g-1 for MO and 305.39 mg. g-1 for IC. The Ti (10 %)@ZnO nanocomposite showed remarkable high stability towards the removal of both dyes through consecutive four cycles.

Optimizing physico-chemical properties of hierarchical ZnO/TiO2 nano-film by the novel heating method for photocatalytic degradation of antibiotics and dye.

The design of semiconductor catalysts with excellent photocatalytic properties, stability, recyclability, and good separation for the treatment of polluted water is still challenging. In this paper, the ZnO/TiO2 nano-thin films were fabricated using the magnetron sputtering technique and then heating the underlying ZnO layer and the upper TiO2 layer for their respective optimal heating time, i. e. heating ZnO for 3 h and heating TiO2 for 2 h. The as-prepared films were characterized. The results show that the preferred growth of TiO2 grains along the [001] axis, relatively large specific surface area, and increased amounts of surface oxygen vacancies (OVs) were induced to the heterojunction catalysts through this optimized heating strategy, which boosts the photocatalytic activity of ZnO/TiO2 nano-film. The degradation experiment inndicates that the ciprofloxacin (CIP) removal efficiency can reach 97.3% in 2 h duration, which was higher than that of the samples annealed for the same periods. Meanwhile, the prepared ZnO/TiO2 photocatalytic film exhibited favorable stability of 95.5% degradation efficiency after the fourth run and general applicability for the photodegradation of various contantains, whih removed 99.5% of ofloxacin (OFX) and 77.6% of tetracycline (TC) in 2 h and 94.1% of Rhodamine B (RhB) in 1 h. This work is expected to yields a novel insight into the production of heterojunction photocatalysts with excellen ability for photocatalytic degradation of pollutants in the practical industry.

Shaping the Structure and Properties of TiO2-ZnO Oxide Coatings Produced by Plasma Electrolytic Oxidation on Titanium Substrate.

The paper presents the results of preliminary research on the possibility of synthesizing ZnO-TiO2 mixed coatings by plasma electrochemical oxidation (PEO). The aim of the work was to synthesize TiO2-ZnO mixed coatings on a titanium substrate from an electrolyte containing ZnO nanoparticles (NPs) and to assess the parameters of PEO on the structure, chemical composition, and properties of the obtained oxide coatings. The PEO process was carried out under various current-voltage conditions using different signals: DC, DC pulse, and AC. In this work, optimal conditions for the PEO process were determined to obtain well-adhering oxide coatings with the highest possible content of ZnO. The structure and morphology of the resulting oxide coatings were investigated, and their chemical and phase composition was comprehensively examined (EDX, XRD, XPS, and GD-OES). In addition, their basic optical properties were assessed. It has been shown that in the PEO DC pulse process, it is possible to obtain oxide coatings characterized by a high degree of structure order, high ZnO content in the oxide coating (3.6 at.%, XPS), and prospective applications for photocatalytic purposes (3.12 eV).

Persulfate-assisted heterogeneous photocatalytic degradation of furfural from aqueous solutions using TiO2-ZnO/biochar composite.

This study evaluated the performance of TiO2-ZnO/biochar as activator of persulfate (PS) for degradation of furfural. After the successful synthesis of the catalyst, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) methods were used to investigate the properties of TiO2-ZnO/biochar. The findings of this research suggests that under optimal conditions (pH = 3, catalyst dosage = 1 g/L, persulfate concentration = 1.2 mM, and furfural concentration = 10 mg/L), the PS/Catalysts/UV system can remove 96 % of furfural within 15 min. Under ideal conditions, the experimental results fit well with the first-order kinetic model (R2 > 0.95), and the rate constant (Kobs) was derived as 0.195 min-1. The quenching experiments provided further insights that confirmed the participation of SO4°- and OH° radicals in the degradation process. Nevertheless, the evidence strongly supports the idea that SO4°- plays a more prominent and dominant role as the primary radical species responsible for furfural degradation. Based on the obtained results, it can be concluded that the PS/Catalysts/UV system has an appropriate ability to remove furfural from aqueous solutions, which suggests promising perspectives for its practical application in pollutant treatment scenarios.

Gas Sensing of Laser-Produced Hybrid TiO2-ZnO Nanomaterials under Room-Temperature Conditions.

The preparation method can considerably affect the structural, morphological, and gas-sensing properties of mixed-oxide materials which often demonstrate superior photocatalytic and sensing performance in comparison with single-metal oxides. In this work, hybrids of semiconductor nanomaterials based on TiO2 and ZnO were prepared by laser ablation of Zn and Ti plates in water and then tested as chemiresistive gas sensors towards volatile organics (2-propanol, acetaldehyde, ethanol, methanol) and ammonia. An infrared millisecond pulsed laser with energy 2.0 J/pulse and a repetition rate of 5 Hz was applied to Zn and Ti metal targets in different ablation sequences to produce two nano-hybrids (TiO2/ZnO and ZnO/TiO2). The surface chemistry, morphology, crystallinity, and phase composition of the prepared hybrids were found to tune their gas-sensing properties. Among all tested gases, sample TiO2/ZnO showed selectivity to ethanol, while sample ZnO/TiO2 sensed 2-propanol at room temperature, both with a detection limit of ~50 ppm. The response and recovery times were found to be 24 and 607 s for the TiO2/ZnO sensor, and 54 and 50 s for its ZnO/TiO2 counterpart, respectively, towards 100 ppm of the target gas at room temperature.

Sustainable Removal of Tolperisone from Waters by Application of Photocatalysis, Nanotechnology, and Chemometrics: Quantification, Environmental Toxicity, and Degradation Optimization.

Environmental pollution is an emerging global issue. Heterogenous photocatalytic degradation, which belongs to the advanced oxidation processes, is a promising sustainable technique for the removal of harmful pollutants (e.g., pharmaceuticals) from natural resources (surface and underground waters), as well as wastewaters. In our study, we examined the efficiency of photocatalytic degradation (with TiO2 and ZnO as photocatalysts) of tolperisone hydrochloride (TLP) and the effect of TLP and its degradation intermediates on germination, photosynthetic capacity, and biomass production of wheat. According to the UFLC-DAD and LC-ESI-MS results, we found that the complete degradation of TLP can be reached after 60.83 min of UV irradiation using TiO2 as a photocatalyst. Furthermore, we determined that germination, biomass production, and chlorophyll b (Chl b) were not related to the percentage of TLP after irradiation. Chlorophyll a (Chl a) (r = -0.61, p ≤ 0.05), Chl a+b (r = -0.56, p ≤ 0.05), and carotenoid (car) (r = -0.57, p ≤ 0.05) were strongly inversely (negatively) correlated with TLP, while Chl a+b/car (r = 0.36, p ≤ 0.05) was moderately (positively) related.

Synthesis and characterization of TiO2/ZnO heterostructural composite for ultraviolet photocatalytic degrading DOM in landfill leachate.

In order to investigate the photocatalytic degradation of dissolved organic matter (DOM) in landfill leachate, TiO2/ZnO heterostructural composite powders were fabricated combining with hydrothermal synthesis and solid-state reaction method. The prepared TiO2/ZnO composite powders consist of anatase TiO2 nanoparticles distributing on the surface of wurtzite ZnO particles. The optical band gap of TiO2/ZnO powder is less than that of pure ZnO or TiO2 powder. TiO2/ZnO catalyzers show high ultraviolet-degradation efficiency for methylene blue and dissolved organic matter. The degradation rate of TiO2/ZnO powder for fulvic acid-like substances in landfill leachate is 2.99 times that of pure ZnO powder, and is 1.30 times that of pure TiO2 powder. The degradation of fulvic acid-like substances by TiO2/ZnO photocatalyst reduced some molecular weight of benzene ring structure substances in leachate. The effective separation of electron and hole in heterostructural TiO2/ZnO photocatalyst is the main reason for its high photocatalytic degradation efficiency of DOM in landfill leachate.

Fabrication of bacterial cellulose with TiO2-ZnO nanocomposites as a multifunctional membrane for water remediation.

Superhydrophilic/underwater superoleophobic (SUS) membrane technology has attracted extensive attention for water purification. However, the fabrication of multifunctional membranes to satisfy the complex wastewater treatment is still a big challenge. In this work, bacterial cellulose (BC) based multifunctional SUS membranes were designed for water purification. Membranes were prepared by blending BC nanofibers with TiO2 nanoparticles (NPs), and further modified by the in situ growth of ZnO-NPs. The composite membranes showed oil/water (o/w) separation under a small driving pressure (0.2-0.3 bar) with a flux rate of 8232.81 ± 212 L m-2h-1 and with a high separation efficiency (>99.9%). Membranes could also separate oil-in-water emulsion with a separation flux of 1498 ± 74 L m-2h-1 and with high efficiency (99.25%). Moreover, the composite membrane exhibited photocatalytic activity under visible light with a high efficiency (>92%). The composite membranes were also investigated for antibacterial activity against Gram-positive and Gram-negative bacterial strains. This work may inspire the fabrication of next-generation multifunctional membranes for wastewater treatment, particularly oily wastewater, dyes and microbial contaminated water.

The effect of near-surface electron trapping layer on the acetone sensing performance of black TiO2capped with ZnO.

In recent years, high-performance acetone gas sensors have attracted great attention for their potential in noninvasive blood glucose monitoring. In this work, black TiO2(B-TiO2) was introduced as an electron trapping layer between TiO2and ZnO to form TiO2@B-TiO2@ZnO core-shell nanoparticles, through a simple and safe method. The acetone sensing performance of TiO2@B-TiO2@ZnO varied with the thickness of ZnO. Because of the electron trapping effect of the introduced B-TiO2layer, the best performing sample exhibited a low optimal operating temperature of 275 °C and a high response of 49.25-50 ppm acetone. In addition, a low detection limit of 170 ppb was obtained. The pretty selectivity of the sample was also been proved. The mechanism of enhanced acetone response was explained by the energy band-based model of TiO2@B-TiO2@ZnO core-shell nanoparticle and depletion layer theory.

Sustainable Green Nanotechnologies for Innovative Purifications of Water: Synthesis of the Nanoparticles from Renewable Sources.

Polluting the natural water resources is a serious global issue, which is confirmed by the fact that today at least 2 billion people consume water from contaminated sources. The conventional wastewater treatment methods cannot effectively remove the persistent pollutants (e.g., drugs, organic dyes, pesticides) from the aqueous environment. Heterogeneous photocatalysis is a promising and sustainable alternative for water remediation. It is based on the interaction between light irradiation and the semiconductors (e.g., TiO2, ZnO) as photocatalysts, but these compounds, unfortunately, have some disadvantages. Hence, great attention has been paid to the nanotechnology as a possible way of improvement. Nanomaterials have extraordinary properties; however, their conventional synthesis is often difficult and requires a significant amount of dangerous chemicals. This concise topical review gives recent updates and trends in development of sustainable and green pathways in the synthesis of nanomaterials, as well as in their application for water remediation. In our review we put emphasis on the eco-friendly, mostly plant extract-based materials. The importance of this topic, including this study as well, is proved by the growing number of publications since 2018. Due to the current serious environmental issues (e.g., global warming, shortage of pure and quality water), it is necessary for the traditional TiO2 and ZnO semiconductors to be replaced with the harmless, non-toxic, and more powerful nanocomposites as photocatalysts. Not only because of their higher efficiency as compared to the bulk semiconductors, but also because of the presence of biomolecules that can add up to the pollutant removal efficiency, which has been already confirmed in many researches. However, despite the fact that the application of heterogeneous photocatalysis together with green nanotechnology is absolutely the future in water purification, there are some challenges which have to be overcome. The exact effects of the biomolecules obtained from plants in the synthesis of nanoparticles, as well as in the photocatalytic processes, are not exactly known and require further investigation. Furthermore, heterogeneous photocatalysis is a well-known and commonly examined process; however, its practical use outside the laboratory is expensive and difficult. Thus, it has to be simplified and improved in order to be available for everyone. The aim of our review is to suggest and prove that using these bio-inspired compounds it is possible to reduce human footprint in the nature.

Fabrication of Pt doped TiO2-ZnO@ZIF-8 core@shell photocatalyst with enhanced activity for phenol degradation.

Phenol's presence in aqueous solution due to the pollution from chemical and agricultural industries (e.g., coking tobacco leaves) causes severe environmental problems. As a result, many scientists and engineers search for catalysts to remove phenol from water by photodegradation. Thus, we synthesized Pt-doped TiO2-ZnO@ZIF-8 core@shell particles (Pt/TiO2-ZnO@ZIF-8) by a simple method involving crystallization, absorption, pyrolysis and growth steps. The resulting materials were analyzed by the powder X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM, respectively), surface area measurements and UV-vis absorption spectroscopy. The photocatalytic activities of our materials were evaluated by phenol degradation in aqueous solutions. Pt-doped TiO2-ZnO particles possessed a polyhedral structure and exhibited broad absorption above 400 nm. Coating with ZIF-8 increased the specific surface area of the Pt-doped TiO2-ZnO particles. Both Pt doping and ZIF-8 coating significantly enhanced the photocatalytic performance of TiO2-ZnO. Pt/TiO2-ZnO@ZIF-8 decomposed 99.7 % of phenol after the corresponding solution was exposed to UV light for 24 min. This performance was significantly better than the phenol decomposition ability of TiO2-ZnO, Pt/TiO2-ZnO and TiO2, which degraded 76.1 %, 95.2 % and 86.9 % of phenol, respectively. Pt/TiO2-ZnO@ZIF-8 also demonstrated excellent recycling stability. All these properties, including photostability, made our novel Pt/TiO2-ZnO@ZIF-8 catalyst a promising material for practical applications in environmental remediation.

Combinatorial selectivity with an array of phthalocyanines functionalized TiO2/ZnO heterojunction thin film sensors.

The development of electronic noses requires the control of the selectivity pattern of each sensor of the array. Organic chemistry offers a manifold of possibilities to this regard but in many cases the chemical sensitivity is not matched with the response of electronic sensor. The combination of organic and inorganic materials is an approach to transfer the chemical sensitivities of the sensor to the measurable electronic signals. In this paper, this approach is demonstrated with a hybrid material made of phthalocyanines and a bilayer structure of ZnO and TiO2. Results show that the whole spectrum of sensitivity of phthalocyanines results in changes of the resistance of the sensor, and even the adsorption of compounds, such as hexane, which cannot change the resistance of pure phthalocyanine layers, elicits changes of the sensor resistance. Furthermore, since phthalocyanines are optically active, the sensitivity in dark and visible light are different. Thus, operating the sensor in dark and light two different signals per sensors can be extracted. As a consequence, an array of 3 sensors made of different phthalocyanines results in a virtual array of six sensors. The sensor array shows a remarkable selectivity respect to a set of test compounds. Principal component analysis scores plot illustrates that hydrogen bond basicity and dispersion interaction are the dominant mechanisms of interaction.

The TiO2-ZnO Systems with Multifunctional Applications in Photoactive Processes-Efficient Photocatalyst under UV-LED Light and Electrode Materials in DSSCs.

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.

Efficacy and reusability of mixed-phase TiO2-ZnO nanocomposites for the removal of estrogenic effects of 17ß-Estradiol and 17α-Ethinylestradiol from water.

Photocatalytic removal of estrogenic compounds (ECs), 17ß-estradiol (E2), and 17α-ethinylestradiol (EE2) were assessed using a TiO2-ZnO nanocomposite (NC) over a range of initial EC concentration (Co; 10 mg/L - 0.05 mg/L). Photocatalytic removal was evaluated under UV and visible irradiation using 10 mg/L NC over 240 min duration. After 240 min, analysis using GCxGC TOF MS revealed 100% transformation at Co ≤ 1 mg/L and ≥25% transformation at Co ≤ 10 mg/L under visible irradiation. Degradation was accompanied by breakdown of the fused ring structure of E2, generating smaller molecular weight by-products which were subsequently mineralized as revealed through TOC removal. With UV photocatalysis, ~30% and ~20% mineralization was attained for E2 and EE2, respectively, for Co of 10 mg/L. Under visible irradiation, ~25% and ~10% mineralization was achieved for E2 and EE2, respectively. Estrogenicity variation was estimated using the E-screen assay conducted with estrogen receptor-positive MCF-7 breast cancer cells. Complete removal of estrogenicity of ECs was confirmed after 240 min of photocatalysis under UV and visible irradiation. FTIR spectroscopy-based analysis of the NC after E2 photocatalysis revealed the presence of sorbed organics. Desorption, followed by GC × GC TOF-MS analysis revealed these organics as by-products of photocatalysis. Desorption of sorbed organics followed by recalcination at 600 °C for 1 h regenerated the active sites on the NC, enabling its efficient reuse for 3 cycles under visible irradiation without loss in activity.

Engineering of mono-dispersed mesoporous TiO2 over 1-D nanorods for water purification under visible light irradiation.

Herein we synthesized a novel structure of mesoporous TiO2 decorated on 1D ZnO nanorods for environmental remediation. The effect of mesoporous TiO2 over 1D nanorods were investigated. The phase transitions of nanocomposite were confirmed by powder diffraction analysis. The morphological investigation of synthesized TiO2/ZnO catalyst revealed that the TiO2 are in porous in nature which covered the surface of 1D nanorods. The size of mesoporous TiO2 nanoparticles was about 10-15 nm. The chemical composition and elemental mapping results clearly evident that the presence of ZnO and TiO2 is distributed uniformly on ZnO nanorods. TiO2/ZnO nanocomposite shows enhanced activity which degrades in 14 min under visible light irradiation. TiO2/ZnO catalyst with 5 wt % exhibited the high photocatalytic activity (0.1882 min-1). It is proposed that a synergistic interaction between ZnO and TiO2 leads to a charge separation which leads to the enhanced activity.

The bactericidal potential of LLDPE with TiO2/ZnO nanocomposites against multidrug resistant pathogens associated with hospital acquired infections.

The emerging polymer nanocomposites have received industrial interests in diverse fields because of their added value in metal oxide-based nanocomposites, such as titanium (TiO2) and zinc oxide (ZnO). Linear low-density polyethylene (LLDPE)-based polymer has recently generated a huge market in the healthcare industry. TiO2 and ZnO are well known for their instant photocatalytic killing of hospital-acquired infections, especially multidrug-resistant (MDR) pathogens. This study investigated the actions of LLDPE/TiO2/ZnO (1:3) nanocomposites in different weight% against two representative MDR pathogens, namely, methicillin-resistant Staphylococcus aureus (MRSA) and Klebsiella pneumonia (K.pneumoniae). Antibacterial activities were quantified according to international standard guidelines of CLSI MO2-A11 (static condition) and ASTM E-2149 (dynamic condition). Preliminary observation via a scanning electron microscope revealed that LLDPE matrix with TiO2/ZnO nanocomposites changed the bacterial morphology and reduced the bacterial adherence and biofilm formation. Furthermore, a high ZnO weight ratio killed both types of pathogens. The bactericidal potential of the nanocomposite is highlighted by the enhancements in photocatalytic activity, zinc ion release and reactive species, and bacteriostatic/bactericidal activity against bacterial growth. This study provides new insights into the MDR-bactericidal potential of LLDPE with TiO2/ZnO nanocomposites for targeted healthcare applications.

Thin-Film Engineering of Mechanical Fragmentation Properties of Atomic-Layer-Deposited Metal Oxides.

Mechanical fracture properties were studied for the common atomic-layer-deposited Al2O3, ZnO, TiO2, ZrO2, and Y2O3 thin films, and selected multilayer combinations via uniaxial tensile testing and Weibull statistics. The crack onset strains and interfacial shear strains were studied, and for crack onset strain, TiO2/Al2O3 and ZrO2/Al2O3 bilayer films exhibited the highest values. The films adhered well to the polyimide carrier substrates, as delamination of the films was not observed. For Al2O3 films, higher deposition temperatures resulted in higher crack onset strain and cohesive strain values, which was explained by the temperature dependence of the residual strain. Doping Y2O3 with Al or nanolaminating it with Al2O3 enabled control over the crystal size of Y2O3, and provided us with means for improving the mechanical properties of the Y2O3 films. Tensile fracture toughness and fracture energy are reported for Al2O3 films grown at 135 °C, 155 °C, and 220 °C. We present thin-film engineering via multilayering and residual-strain control in order to tailor the mechanical properties of thin-film systems for applications requiring mechanical stretchability and flexibility.

Hybrid TiO2-ZnO Nanomaterials Prepared Using Laser Ablation in Liquid.

Hybrids of semiconductor nanomaterials often demonstrate properties that are superior to those of their components. In this study, we prepared hybrid nanomaterials of TiO2 and ZnO, which are among the most actively studied semiconductors, by means of millisecond-pulsed laser and analyzed how their morphology, particle size, and surface composition depend on preparation conditions. A series of nanomaterials were obtained via sequentially ablating Zn and Ti metal plates (in different sequences) in water, while laser pulses of lower (2.0 J/pulse) and higher (5.0 J/pulse) energy were applied. The properties of laser-produced hybrid TiO2-ZnO nanomaterials were shown to be governed by experimental conditions such as laser pulse width, pulse peak power, and reaction media (either pure water or colloid with nanoparticles). The morphology revealed nanospheres of TiO2 that decorate nanorods of ZnO or flower-like aggregates of zinc oxide. Intriguingly, after extended ablation time, titania was found to be self-doped with Ti3+ and Ti2+ ions, and the contribution of lower oxidation states of titanium could be controlled by the applied laser pulse energy. The physicochemical characteristics of hybrid nanomaterials were compared with pure ZnO and TiO2 prepared under the same laser conditions.

Synthesis of sewage sludge-based carbon/TiO2 /ZnO nanocomposite adsorbent for the removal of Ni(II), Cu(II), and chemical oxygen demands from aqueous solutions and industrial wastewater.

The removal of heavy metal ions and organic materials from wastewater due to their toxicity is necessary. In the present study, the titanium dioxide/zinc oxide (TiO2 /ZnO) nanocomposite has been coated on the sewage sludge carbon (SSC) surface and its application was investigated for the adsorption of Ni(II), Cu(II), and chemical oxygen demands (COD) reduction from aqueous solutions and industrial wastewaters in Eshtehard, Iran. The effect of adsorption parameters in a single system such as TiO2 /ZnO ratio, TiO2 /ZnO concentration, pH, adsorbent dosage, contact time, ionic strength, temperature, and initial concentrations of Ni(II), Cu(II), and COD was investigated on the adsorption capacity of synthesized SSC/TiO2 /ZnO adsorbent. The pseudo-second order and Redlich-Peterson isotherm models were best described the kinetic and equilibrium data of Ni(II), Cu(II), and COD sorption. The maximum monolayer sorption capacities of Ni(II), Cu(II), and COD were found to be 62.3, 75.1, and 1,120.3 mg/g, respectively. The central composite design was used to investigate the interaction effects of pH and initial concentrations of Ni(II), Cu(II), and COD on the simultaneous removal of Ni(II), Cu(II), and COD from aqueous solutions in a ternary system. The potential of synthesized SSC/TiO2 /ZnO adsorbent was investigated for Ni(II), Cu(II), and COD adsorption from industrial wastewaters of Iran. PRACTITIONER POINTS: The novel sewage sludge carbon/TiO2 /ZnO adsorbent was synthesized. Adsorption of Ni(II), Cu(II), and chemical oxygen demands (COD) from industrial wastewaters was investigated. Maximum Ni(II), Cu(II), and COD sorption capacities were 62.3, 75.1, and 1,120.3 mg/g. Simultaneous removal of Ni(II), Cu(II), and COD was investigated in a ternary system.