Growth Of ZnO Nanoparticles Research Articles

Growth of ZnO nanorods/flowers on the carbon fiber surfaces using sodium alginate as medium to enhance the mechanical properties of composites

The chemical inertness of the carbon fiber (CF) surface results in suboptimal mechanical properties of the prepared composites. To address this issue, we employed a combination of tannic acid and 3-aminopropyltriethoxysilane mixture (TA-APTES) grafted sodium alginate (SA) as a medium to enhance the interfacial properties of composites through the growth of ZnO nanoparticles on CF surfaces. ZnO nanolayers with rod-like and flower-like structures were obtained by adjusting the pH of the reaction system (pH = 10 and 12, respectively). Characterization results show that in comparison with the untreated CF composites, in the flexural strength, flexural modulus, interlaminar shear strength (ILSS) and interfacial shear strength (IFSS) of the as-prepared CF/TA-APTES/SA/ZnO10 (nanorods) composites were improved by 40.8 %, 58.4 %, 44.9 % and 47.8 %, respectively. The prepared CF/TA-APTES/SA/ZnO12 (nanoflowers) composite showed an increase in flexural strength, flexural modulus, ILSS and IFSS by 39.8 %, 63.6 %, 47.3 % and 48.2 %, respectively. These positive results indicate that the ZnO nanolayers increase the interfacial phase area and fiber surface roughness, thereby enhancing mechanical interlocking and load transfer between the fibers and resin matrix. This work provides a novel interfacial modification method for preparing CF composites used in longer and more durable wind turbine blades.

Green Mediated Synthesis of Zinc Oxide Nanoparticles using Tamarind Bark Extract and their Applications in Textile Dye Degradation and Antimicrobial Studies

ZnO nanoparticles were synthesized using tamarind bark extract as a green reducing agent in alkaline medium. The tamarind bark solution acts both as a stabilizing and a reducing agent which regulates the size and the shape of the green synthesized zinc oxide nanoparticles. The progressive growth of ZnO nanoparticles was monitored by using UV-visible spectral studies. A sharp peak at 349 nm indicates the formation of spherical shaped zinc oxide nanoparticles. The size and shape of the ZnO nanoparticles were observed using scanning electron microscopy (SEM). The catalytic behaviour of a ZnO nanoparticle was studied for the degradation of textile dyes like methylene blue and Congo red and observed that the degradation reaction follows pseudo first-order kinetics with a rate constant k =0.0331 min-1, 0.0283 min-1 and 0.1175 min-1, 0.1167 min-1, respectively for ZnO nanoparticles at 50 µg and 100 µg. The antimicrobial activity of ZnO nanoparticles was also tested for various Gram-positive, Gram-negative bacteria and fungi in which higher zone of inhibition was observed for Gram-negative microorganism.

Relevance of alcoholic solvents in the growth of ZnO nanoparticles and ZnO hierarchical nanorod structures on their optical and opto-electrical properties

We report on the synthesis of ZnO nanoparticles and ZnO hierarchical nanorod structures using four different alcohols i.e. methanol, isopropanol, ethanol, and aqueous ethanol (70% alcohol, 30% water). The syntheses of the nanoparticles were carried out by non-aqueous and hydrothermal routes. In general, absolute alcohol allows a better control of the synthesis reaction and nanoparticles as small as 5 nm were obtained, confirmed by TEM. XPS analysis elucidated the chemical states that were correlated to the synthesis reaction. For the nanorod growth, these four alcohols were used as seeding solvents, followed by hydrothermal ZnO nanorod growth. Here, the seed layer tailored the nanorod diameters and surface defects, which were studied by SEM and photoluminescence spectroscopy. Subsequently, the ZnO nanorods were electrically characterized and exhibited persistent photoconductivity under UV irradiation of 365 nm. The differences in conductivity in dark and under UV irradiation were attributed to the size of the nanorods, defect states, semiconductor band bending and oxygen adsorption–desorption mechanisms. Parameters such as photoresponse and photosensitivity are also calculated in order to evaluate their applicability in UV sensors. This work demonstrates optimization of the physical, chemical, electrical and optical properties of both ZnO nanostructures via the use of alcoholic solvents.

In Situ Ultra-Small- and Small-Angle X-ray Scattering Study of ZnO Nanoparticle Formation and Growth through Chemical Bath Deposition in the Presence of Polyvinylpyrrolidone.

ZnO inverse opals combine the outstanding properties of the semiconductor ZnO with the high surface area of the open-porous framework, making them valuable photonic and catalysis support materials. One route to produce inverse opals is to mineralize the voids of close-packed polymer nanoparticle templates by chemical bath deposition (CBD) using a ZnO precursor solution, followed by template removal. To ensure synthesis control, the formation and growth of ZnO nanoparticles in a precursor solution containing the organic additive polyvinylpyrrolidone (PVP) was investigated by in situ ultra-small- and small-angle X-ray scattering (USAXS/SAXS). Before that, we studied the precursor solution by in-house SAXS at T = 25 °C, revealing the presence of a PVP network with semiflexible chain behavior. Heating the precursor solution to 58 °C or 63 °C initiates the formation of small ZnO nanoparticles that cluster together, as shown by complementary transmission electron microscopy images (TEM) taken after synthesis. The underlying kinetics of this process could be deciphered by quantitatively analyzing the USAXS/SAXS data considering the scattering contributions of particles, clusters, and the PVP network. A nearly quantitative description of both the nucleation and growth period could be achieved using the two-step Finke-Watzky model with slow, continuous nucleation followed by autocatalytic growth.

In Situ Pressure Controlled Growth of ZnO Nanoparticles: Tailoring Sizes, Defects, and Optical Properties.

ZnO, being an inexpensive, wide band gap semiconductor that possesses high mechanical, thermal, and chemical stabilities and suitable for a wide range of optical and electronic applications, is the preferred semiconductor of this era. In an effort to fully utilize its potential features, ZnO research is receiving increasing attention. This study investigates the influence of pressure on the crystallinity, defect density, size, and morphology of ZnO nanoparticles, synthesized using nonaqueous sol-gel method, and their respective impact on the optical properties. High-crystalline ZnO nanocrystals with a hexagonal wurtzite structure were synthesized at various pressures, including ambient pressure, 25, 37.5, 50, and 100 bars inside a high-pressure reactor. With the increase in pressure, a reduction in particle size was observed, reaching a minimum size (∼10 nm) at 50 bar pressure (ZnO-50). Further increase in pressure causes an enhancement in the particle size. This trend of size variation with pressure is attributed to a tradeoff between esterification and nucleation processes. Contrary to the expectation, smaller ZnO nanocrystals synthesized by the present method possess lesser number of defects, suggesting that high-pressure synthesis is a unique way that offers smaller ZnO nanocrystals of sub-10 nm sizes having high crystallinity and lesser defects in a shorter time span. Also, the optical transmittance of the systems could be greatly enhanced by carefully tuning the particle sizes, with ZnO-50 (∼10 nm particle size) having the highest transmittance (∼95% at 600 nm) among all samples. High crystallinity, uniform morphology, excellent visible transparency, wide band gap, and low defect density make these smaller ZnO nanocrystals a preferred choice for ultraviolet sensors and other optoelectronic devices.

Facile preparation of cellulose nanocrystals/ZnO hybrids using acidified ZnCl2 as cellulose hydrolytic media and ZnO precursor

Hybridization of nanocellulose with zinc oxide nanoparticles can improve the dispersibility of the zinc oxide and bring new functions to the bio-based products. In this study, cellulose nanocrystal/zinc oxide (CNC/ZnO) nanohybrids with reinforcing and antibacterial properties were prepared via a facile one-pot route. Microcrystalline cellulose (MCC) was first treated with acidified zinc chloride and hydrolyzed into CNCs, which then served as a stabilizing and supporting agent for the in-situ growth of ZnO nanoparticles during subsequent chemical precipitation. The acidified ZnCl2 solution played a dual role, acting both as cellulose hydrolytic media and as ZnO precursor. By adjusting the pH of the zinc precursor solution (pH = 9–12), well-dispersed rod-like (length: 137.0–468.0 nm, width: 54.1–154.1 nm) and flower-like (average diameter: 179.6 nm) ZnO nanoparticles with hexagonal wurtzite structure were obtained. CNC/ZnO nanohybrids were incorporated into waterborne polyurethane (WPU) films. The Young's modulus and tensile strength of the nanocomposite films increased gradually from 154.8 to 509.0 MPa and from 16.5 to 29.9 MPa, respectively, with increasing CNC/ZnO nanofiller content up to 10 wt%. The 10 % CNC/ZnO composites showed inhibition rates to both E. coli and S. aureus above 88.8 %.

Boron nitride nanosheets modified with zinc oxide nanoparticles as novel fillers of dental resin composite

ObjectiveThe purpose of this study was to synthesize boron nitride nanosheets modified with zinc oxide nanoparticles (BNNSs/ZnO) and incorporate them as a novel inorganic filler to get an antibacterial dental resin composite. MethodsThe BNNSs/ZnO nanocomposites were synthesized via the hydrothermal method and characterized by Field Emission Scanning Electron Microscope (FESEM), Transmission Electron Microscopy (TEM), Energy Dispersive Spectrometer (EDS), X-ray Diffraction (XRD) and Fourier Transform-Infrared (FTIR) Spectroscopy. The BNNSs/ZnO or BNNSs were added into the experimental dental composite with different proportions, respectively. The mechanical and physical properties of the modified dental composite were evaluated. Their antibacterial activities were also assessed by quantitative analysis using Streptococcus mutans (S. mutans). ResultsThe BNNSs/ZnO nanocomposites were successfully synthesized, and the growth of ZnO nanoparticles (ZnO NPs) on boron nitride nanosheets was confirmed. The flexural strength (FS), flexural modulus (FM) and the compressive strength (CS) of all modified resin composites showed no change compared to the control group. The curing depth, degree of conversion, water absorption and solubility of the modified composites were still within the clinical requirement. The antibacterial rates of the modified composites were significantly increased compared to the control group, which can reach 98 % when 0.5 % BNNSs/ZnO was added. SignificanceThe modified dental resin composite with novel BNNSs or BNNSs/ZnO fillers shows significantly high antibacterial activity with suitable physicochemical and mechanical properties.

Superamphiphobic cotton fabric with photocatalysis and ultraviolet shielding property based on hierarchical ZnO/halloysite nanotubes hybrid particles

The combination of photocatalysis and superamphiphobic cotton fabric has attracted extensive attention as it can not only repel the millimeter-scale contaminant droplets in daily life, but also photodegrade the micro-droplet pollutants with ultralow surface tension d in light. However, its invention is a great challenge. In this work, superamphiphobic cotton fabrics with photocatalysis and ultraviolet (UV) shielding property were fabricated based on fluorinated ZnO/halloysite nanotubes (HNTs) hybrid particles with micro/nano hierarchical structures and photocatalytic activity. The ZnO/HNTs hybrid particles were prepared by in-situ growth of ZnO nanoparticles on the surface of halloysite nanotubes (HNTs) with unique needlelike microstructure, high aspect ratio, eco-friendliness, low cost, biocompatibility, and abundance in nature. The fluorinated ZnO/HNTs (F-ZnO/HNTs) based on ZnO/HNTs were sprayed onto cotton fabrics to obtain superamphiphobic cotton fabrics with ultraviolet (UV) shielding and photocatalysis. The as-obtained cotton fabrics could repel common liquids in daily life even with low surface tension (the rapeseed oil contact angle was 154.3 ± 0.9°), exhibiting excellent superamphiphobic self-cleaning and antifouling properties. About 89 % of methylene orange was degraded after being irradiated by UV lamp for 4 h, indicating that the coated cotton fabric had excellent photocatalytic activity. Importantly, after 1500 cycles of mechanical abrasion, 60 h UV illumination or1h of immersion in acidic and alkali solutions, the coated cotton fabrics retained superamphiphobic performance. Due to the synergistic effect of the superamphiphobic and photocatalytic performance, the obtained cotton fabrics showed potential applications in various promising fields.

Hydrothermal growth of ZnO nanoparticles on the surface of two kinds of Ti 3 C 2 co‐catalysts with different interlayer spacing towards enhanced photocatalytic activity

Hydrothermal growth of ZnO nanoparticles on the surface of two kinds of Ti ₃ C ₂ co‐catalysts with different interlayer spacing towards enhanced photocatalytic activity

Gradual growth of ZnO nanoparticles from globules-like to nanorods-like shapes: Effect of annealing temperature

We report the microstructure, optical properties and high photocatalytic performance, with correlations between them, of coprecipitated and post-annealed ZnO nanoparticles. The obtained ZnO single phase after post annealing at different temperatures (200–600 °C) was identified by X-ray diffraction (XRD) and its morphology was investigated by transmission electron microscopy (TEM). The TEM results indicate a gradual growth of the spherical-like nanoparticles to nanorod-like shapes by post annealing with common nanorods shape by annealing at 600 °C. XRD Rietveld refinements indicated that the global structure parameters such as lattice constants, bond lengths, and oxygen position are slightly affected by the post annealing. While the crystallite size and number of unit cells per a particle gradually increase, the dislocation density, micro-strain and residual stress gradually decrease by the post annealing with a further change at annealing temperature of 500 °C, indicating correlations to the particles shape. Based on optical absorbance measurements, it was found that the optical energy gap gradually decreases from 3.22 to 2.89 eV by increasing the annealing temperature up to 600 °C. After a period up to 90 min of irradiation, photo-catalytic efficiency of up to 95 % was observed in the photo-degradation of methylene blue. In addition, the nanoparticles annealed at low temperature showed better performance in the photo-degradation of methylene blue. The observed high photocatalytic performance is discussed in correlation to the microstructure and optical properties of the investigated samples.

Robust ZnO/HNTs-based superhydrophobic cotton fabrics with UV shielding, self-cleaning, photocatalysis, and oil/water separation

In this work, robust superhydrophobic cotton fabrics with ultraviolet (UV) shielding, self-cleaning, photocatalysis, and oil/water separation were successfully prepared based on micro/nano hierarchical ZnO/HNTs (halloysite nanotubes) hybrid particles and silicone elastomer polydimethylsiloxane (PDMS). ZnO/HNTs hybrid particles were prepared by in-situ growth of ZnO nanoparticles on the surface of halloysite nanotubes (HNTs). ZnO/HNTs hybrid particles and PDMS were used to successively coat cotton fabrics by dip-coating approach. The coated cotton fabrics displayed excellent superhydrophobicity with a water contact angle (WCA) of 162.5 ± 1.0° owing to the roughness provided by micro/nano hierarchical ZnO/HNTs hybrid particles and low surface energy achieved by PDMS. After being exposed to the UV lamp for 5 h, about 90.8% of the methylene blue was degraded, indicating that the coated cotton fabrics had excellent photocatalytic activity. The as-prepared cotton fabrics also displayed outstanding self-cleaning and antifouling properties. In addition, due to both superhydrophobic and superoleophilic characteristics, the as-prepared cotton fabrics could be used to separate several oil/water mixtures and showed good recoverability. The superhydrophobic cotton fabrics also exhibited excellent UV shielding performance with a large ultraviolet protection factor (UPF) of 1643.28 due to strong ultraviolet-absorption, light scattering and frequent light reflection of ZnO nanoparticles from ZnO/HNTs composites coated on cotton fabrics. Importantly, the as-prepared cotton fabrics retained superhydrophobic performance after 2000 cycles rubbing, 90 h UV illumination, and immersing in acidic and alkali solutions with different pH values ranging from 1 to 14 for 1 h. These characteristics made multifunctional cotton fabrics a satisfactory candidate in various promising fields.Graphical abstract

Study of photocatalytic degradation efficiency of rGO/ZnO nano-photocatalyst and their performance analysis using scanning Kelvin probe

In this work, an efficient reduced graphene-oxide/zinc-oxide (rGO/ZnO) nano-photocatalyst was synthesized via an eco-friendly hydrothermal method to degrade organic dye under visible light exposure and analyzed with Scanning Kelvin Probe (SKP). Prepared samples were characterized via X-ray diffraction (XRD), Field emission-scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform-infrared spectroscopy (FTIR), and UV-Visible absorption spectrophotometer. Structural, morphological, and topological studies revealed the crystal growth of ZnO nanoparticles on rGO as evidenced from XRD, FESEM, and TEM images. UV-Vis studies show the decrease in bandgap energy of rGO/ZnO after the heterostructure formation. UV results confirm the enhanced photodegradation of RhB aqueous solution under visible light. The work function (ɸ) of rGO, ZnO, rGO/ZnO is determined in dark and light conditions by using Scanning Kelvin probe microscopy and discussing their contribution to the photocatalytic process. The novelty of this work is the SKP technique which was used to analyze the degradation mechanism of RhB in the presence of rGO/ZnO catalyst. It is a new way to find out the carrier transport mechanism at the surface of materials with the recorded work function mapping. Photocatalytic activity of rGO/ZnO has shown the maximum degradation of 97% for RhB (pH 7). Our results indicate that more electrons have moved at the catalyst surface and reacted with organic impurities due to larger surface area, which is responsible for suppressing the recombination of photo-induced carriers.

In-vitro evaluation and antibacterial activity of ZnO nanoparticles deposited on hydroxyapatite tablets by RF magnetron sputtering

RF magnetron sputtering was successfully applied in this study to deposit ZnO nanoparticles on hydroxyapatite tablets. Field emission scanning electron microscopy (FE-SEM) images showed the growth of ZnO nanoparticles with a grain size of ∼ 20 nm. Sedimentation occurred on the surface of samples after their immersion in simulated body fluid. Energy dispersive spectroscopy (EDS) analysis, confirmed the presence of Ca, P, Zn, and O elements, while MAP analysis indicated the uniform distribution of hydroxyapatite and ZnO elements. Atomic force microscopy (AFM) revealed lower surface roughness in the coated samples as compared to their uncoated counterparts. The root means square of roughness decreased with the ZnO coating. X-ray diffraction (XRD) results suggest the presence of the ZnO and hydroxyapatite phases. Antibacterial assay of ZnO-coated and uncoated tablets indicated the higher bioactivity of ZnO-coated tablets against E. coli. The atomic absorption spectrophotometry (AAS) and flame photometer results showed the release of Zn2+ and Ca2+ ions from the samples, respectively. During 14 days of immersion in simulated body fluid (SBF), Due to corrosion and destruction of the surface of the samples the Ca2+ concentration of ZnO-coated and uncoated samples, as well as the concentration of Zn2+ ions of ZnO-coated samples exhibited an increase.

Low-Temperature Growth of ZnO Nanoparticles by Using Autoclave

Low-Temperature Growth of ZnO Nanoparticles by Using Autoclave

Mechanistic insights into the anisotropic growth of ZnO nanoparticles deciphered through 2D size plots and multivariate analysis.

The control and understanding of the nucleation and growth of nano-objects are key points for improving and/or considering the new applications of a given material at the nanoscale. Mastering the morphology is essential as the final properties are drastically affected by the size, shape, and surface structure. Yet, a number of challenges remain, including evidencing and understanding the relationship between the experimental parameters of the synthesis and the shape of the nanoparticles. Here we analyzed jointly and in detail the formation of anisotropic ZnO nanoparticles under different experimental conditions by using two different analytical tools enabling the analysis of TEM images: 2D size plots and multivariate statistical analysis. Well-defined crystalline ZnO nanorods were obtained through the hydrolysis of a dicyclohexyl zinc precursor in the presence of a primary fatty amine. Such statistical tools allow one to fully understand the effect of experimental parameters such as the hydrolysis rate, the mixing time before hydrolysis, the length of the ligand aliphatic chain, and the amount of water. All these analyses suggest a growth process by oriented attachment. Taking advantage of this mechanism, the size and aspect ratio of the ZnO nanorods can be easily tuned. These findings shed light on the relative importance of experimental parameters that govern the growth of nano-objects. This general methodological approach can be easily extended to any type of nanoparticle.

Anisotropic growth of ZnO nanoparticles driven by the structure of amine surfactants: the role of surface dynamics in nanocrystal growth.

Herein, we elucidate the key role of amine surfactants in the controlled anisotropic growth of ZnO nanoparticles that is achieved under mild conditions by organometallic hydrolysis. The structuring influence of alkyl substituents on the nitrogen atom of amines is jointly analyzed theoretically by DFT modeling, and experimentally by multinuclear NMR (1H, 13C and 17O) spectroscopy. We demonstrate that in initial steps leading to the growth of colloidal ZnO particles, the nature of molecular species that are involved in the solution strongly depends on the structure of the amine surfactant. By using tertiary, secondary or primary amines, no or weak adducts between the amine and zinc, or stable adducts, or adduct oligomers were identified, respectively. Afterwards, following the course of the reaction, the dynamic behavior of the amines on the grown ZnO nanocrystal surfaces is also strongly correlated with their structure. We identified that in the presence of tertiary, secondary or primary amines, no significant [Zn⋯N] adsorption, or surface adsorption with notable surface mobility, or a very strong adsorption is achieved, respectively. The last case, primary amines, significantly involves the structuring of a hydrogen bonding network. Therefore, such surface dynamic behavior has a predominant role in driving the nanocrystal growth, and orienting the ZnO material final morphology. By forming hydrogen bonds at the nanoparticle surface during the growth process, primary amines specifically lead to the formation of nanorods. Conversely, isotropic nanoparticles and aggregates are obtained when secondary and tertiary amines are used, respectively. These findings shed light on the role of weak surface interactions, herein H-bonding, that rule the growth of nano-objects and are as such crucial to identify, study, and control for achieving progress in nanoscience.

Solid-State Synthesized BiFeO3 Perovskite-Based Fast-Response White-Light Photodetector

This letter reports an indium doped tin oxide (ITO)/ZnO nanoparticles (NPs)/ BiFeO3 ferroelectric perovskite /poly (3, 4-ethylene dioxythiophene): polystyrene sulfonate (PEDOT: PSS)/Ag heterostructure based white-light photodetector. ZnO nanoparticles are synthesized using the sol-gel process, whereas solid-state route method is used for synthesizing BiFeO3. The X-ray diffraction (XRD) of ZnO nanoparticles and BiFeO3 thin film confirms the formation of the wurtzite hexagonal structure of ZnO NPs and the rhombohedral structure of BiFeO3 perovskite. The high-resolution scanning electron microscopy (HR-SEM) of the films confirm the highly dense and uniform growth of ZnO nanoparticles and BiFeO3. The measured responsivity characteristics over 400-750 nm show the maximum responsivity of ~34 mA/W over the wavelength of 450 to 650 nm at an applied bias voltage of 2 V. The photodetector exhibits a reasonably fast light response with the rise time of 7.21 s and fall time of 6.23 s.

PVDF composite membrane with robust UV-induced self-cleaning performance for durable oil/water emulsions separation

Membranes with special wettability (superhydrophobic/superoleophilic or superhydrophilic/superoleophobic) had been introduced to separate oil/water emulsions. Nevertheless, the surface or pore canals of membrane easily fouled by oily wastewater are the tough challenges towards longtime application. In this work, a PVDF@PDA@ZnO membrane was firstly fabricated via growth of ZnO nanoparticles from ZnO seeds planted on the PVDF@PDA membrane. This PVDF@PDA@ZnO membrane showed good separation capability for various emulsions (which the separation efficiencies and fluxes were up to 99.1% and 654 L m − 2h − 1, respectively). The degradation rate of MB solution treated by the composite membrane was almost 100% attributing to the excellent photocatalytic ability of ZnO. Moreover, the composite membrane could maintain high efficiency (above 99.27%) after long-time emulsions separation/UV-light irradiation, which displayed superior UV-driven self-cleaning and oxidation resistance performance. This self-cleanable composite membrane possessed durability and held high promise for long-time oil/water emulsions separation.

In-situ one pot synthesis of graphene-ZnO nanohybrid and its application to UV light detection

The development of molecular/nanoscale level assemblies allows the foundation of many potential novel applications. Chemical approach is one of the most favoured techniques to manipulate the nano-materials in a controllable manner. Herein, we report a simple and reliable one pot technique for preparing graphene-ZnO nanohybrid by coordinating zinc metal ions from precursor, which further led to the growth of ZnO nanoparticles on graphene sheets. The developed heterostructures were characterized through X-ray diffractometry, Fourier transformed infra-red (FTIR) spectroscopy, UV-visible spectroscopy and field emission scanning electron microscopy (FESEM). Morphological details revealed the dense loading of ZnO nanoparticles onto the surface of graphene. The nanohybrid was found to be electrically more responsive to the incident UV light compared to ZnO nanoparticles alone. The proposed method can lead to the fabrication of highly sensitive flexible light detector.

Performance of ZnO/chitosan nanocomposite films for antimicrobial packaging applications as a function of NaOH treatment and glycerol/PVOH blending

Abstract The current study investigates the performance of chitosan-based ZnO nanocomposite films for antimicrobial packaging applications. ZnO nanoparticles are fabricated from zinc acetate solutions and added in plain chitosan and chitosan/glycerol-, chitosan/poly(vinyl alcohol)- blends at 3, 5 and 7 wt. %. Characteristic diffraction peaks at 31.6°, 34.3° and 36.2° confirm the successful formation and growth of ZnO nanoparticles in chitosan-based films after their immersion in hot NaOH solution. Poly(vinyl alcohol) supports the growth of ZnO in chitosan chains and results in higher strain at break and increased barrier. The antimicrobial activity of the nanocomposite films is high against Brevibacterium lactofermentum, moderate against Escherichia coli and almost absent against Corynobacterium glutamicum. Positive synergies between chitosan-based matrices and ZnO nanoparticles are not however established in terms of antimicrobial properties due to the immersion of the films in NaOH solution which lowers the polycationic character and the solubility of chitosan.