Zinc Oxide Nanomaterials Research Articles

Progress in ZnO Nanosensors.

Developing various nanosensors with superior performance for accurate and sensitive detection of some physical signals is essential for advances in electronic systems. Zinc oxide (ZnO) is a unique semiconductor material with wide bandgap (3.37 eV) and high exciton binding energy (60 meV) at room temperature. ZnO nanostructures have been investigated extensively for possible use as high-performance sensors, due to their excellent optical, piezoelectric and electrochemical properties, as well as the large surface area. In this review, we primarily introduce the morphology and major synthetic methods of ZnO nanomaterials, with a brief discussion of the advantages and weaknesses of each method. Then, we mainly focus on the recent progress in ZnO nanosensors according to the functional classification, including pressure sensor, gas sensor, photoelectric sensor, biosensor and temperature sensor. We provide a comprehensive analysis of the research status and constraints for the development of ZnO nanosensor in each category. Finally, the challenges and future research directions of nanosensors based on ZnO are prospected and summarized. It is of profound significance to research ZnO nanosensors in depth, which will promote the development of artificial intelligence, medical and health, as well as industrial, production.

Investigation and prediction of ethylene Glycol based ZnO nanofluidic heat transfer versus magnetic effect by deep learning

In this study, ZnO (zinc oxide) nanoparticle production was performed. Heat transfer coefficients (h) were measured for Ethylene Glycol Based ZnO nanofluids that were produced using pure water, ethanol, and ethylene glycol materials. In the literature, this is the first study in which Nanofluid was produced and experimental results were estimated by using LSTM and CNN-LSTM deep learning models. The study graphs’ show the relationship between heat transfer coefficients. Besides, Reynolds numbers were drawn and predictive models were created by using the LSTM and CNN-LSTM deep learning models for h values of nanofluids. In addition, the deep learning architecture that predicts the effects of the magnetic effect on the heat transfer coefficient has been introduced to the literature as an innovation. The results showed that the heat transfer coefficients can be estimated with the LSTM and CNN-LSTM deep learning model with an average error of 0.7342% and 0.2001% respectively. In addition, the relative error of the heat transfer coefficients as a result of the magnetic effect was determined as 0.02944 and 0.01701, respectively, with the same methods and model. Applying the magnetic effect to the system, an irregularity was observed in the flow and as a result of increased heat transfer, the friction on the pipe wall increased. The importance of the study is modeling the heat transfer coefficient values depending on the different pH values that were used during the synthesis of ZnO nanomaterial and observing the effects of the magnetic effect on the system.

Potential eco-friendly Zinc Oxide nanomaterials through Phyco-nanotechnology –A review

The physico-chemical methods of synthesizing the nanoparticles which are expensive and involve harmful substances are exuded to the environment. Hence, green synthesis of nanoparticles with low cost, non-toxic and eco-friendly advances currently into new research. Amidst the metal oxides, ZnO nanoparticles are synthesized using various biological species that have tremendously increased for various applications. This review details on algae intervened synthesis of ZnO nanoparticles used for numerous biological applications such as antimicrobial, cytotoxicity, antioxidant, larvicidal, and photocatalytic activities. • Synthesis of ZnO nanoparticles using various algal extract. • Shape and size of the nanoparticles were reported using various characterizations. • Various biological applications were included in this review article.

Application value of different dimension ZnO nano materials in sports rehabilitation of basketball players with limb fracture injury

The process of basketball is often accompanied by physical injury, serious fractures of limbs will also occur. At present, the most common treatment for limb fracture is surgery, which can repair the fracture site and achieve the ideal treatment effect through the postoperative sports rehabilitation training. But even so, there are still some difficult problems such as high postoperative infection, most complications, loosening of fixed points, etc. the main solution is to add zinc oxide nano material coating in the implant to reduce infection. However, the current research on the application of different dimensions of ZnO nanomaterials in postoperative sports rehabilitation is almost zero. To solve this problem, this paper will take this as the main research purpose. Through the establishment of the corresponding experimental program, this paper first screened the experimental samples, and randomly divided 30 patients who met the experimental conditions. And divided into zero dimensional group, one-dimensional group and two-dimensional group. Through different groups, the members of each group were coated with different dimensions of ZnO nano materials. This paper unifies the operation standard, the postoperative rehabilitation program, and the corresponding evaluation indicators. Through the way of quantitative indicators, we try to analyze the impact of different dimensions of zinc oxide nano material coating on the postoperative rehabilitation of fracture surgery. According to the experimental data, different dimensions of ZnO nanomaterials have little effect on the success rate of the operation, but there are significant differences in the aspect of anti-infection. Zero dimensional materials performed well in the experiment. Compared with one and two-dimensional groups, the rehabilitation time was shortened and complications were effectively reduced. In this paper, it is suggested that the use of zero dimensional ZnO nanomaterials in fracture surgery is a treatment plan that can be popularized.

Different dimension ZnO nano materials in the rehabilitation of patients with limb fracture and injury

With the rapid development of industry and transportation in China, the incidence rate of open fracture caused by high energy injuries such as traffic accidents and falling height is increasing year by year. Based on the above background, the purpose of this paper is to study the application of ZnO nano materials with different dimensions in the rehabilitation of patients with limb fracture injury. In order to further solve the problem of limb fracture rehabilitation, zinc oxide nanomaterials are applied to fracture rehabilitation in this paper. The application of zinc oxide nanomaterials in fracture rehabilitation is realized by its strong antibacterial, high-efficiency stability and rich and colorful structure. In this paper, we propose to use the unique physical and chemical properties of ZnO nanomaterials to prepare artificial bone, bone cement, external fixation with good osteogenic performance and antibacterial performance, and carry antibiotics for the treatment of open fracture infection and bone defect. During the experiment, compared with other materials, the infection rate of external fixation was only 63%, and the inflammation index of artificial bone was only 2 mg/dl, which was far less than other materials. Moreover, using the excellent plasticity of ZnO nanomaterials, the oriented ZnO nanotube films were prepared, and the effect of inhibiting scar formation was confirmed through experimental research. In this paper, the unique physical, chemical and biological characteristics of zinc oxide nanomaterials were used to creatively introduce them into the treatment of infectious bone defect and injury rehabilitation caused by limb fracture. Through a series of in vitro and animal in vivo experiments, it was proved that zinc oxide nanomaterials can be used as ideal materials for the treatment of infectious bone defect, which provides new zinc oxide nanomaterials to solve clinical problems A new way of thinking.

Biosynthesis of Zinc Oxide Nanoparticles Using Catharanthus roseus Leaves and Their Therapeutic Response in Breast Cancer (MDA-MB-231) Cells

Zinc oxide nanomaterials are effective in cancer treatments, including the destruction of tumor cells with minimal damage to healthy cells. In the study, the biologically synthesized (Catharanthus roseus) zinc oxide nanomaterials with a broad 18-30 nm range were produced and the toxicity of zinc oxide nanomaterials was checked in vitro in the human breast cancer line MDA-MB-231. Inverse relation of the percentage of viable cells to the concentration of zinc oxide nanomaterials at increasing molar levels was assessed. The cytotoxicity analysis used in the MTT test shows the substantial viable MDA-MB-231-cells despite the increased concentration of exposure to zinc oxide nanomaterials. Reduction in the ratio of viable MDA-MB-231 cells after being exposed to zinc oxide nanomaterials was compared to untreated cancerous cells. The present approach to biosynthesis is quick, inexpensive, eco-friendly, and high-rise stable nanomaterials of zinc oxide with substantial cancer potential. This is the first study that reports molar concentrations as an anticancer agent for breast cancer and potential clinical uses for synthesized zinc oxide nanomaterials.

Nanoceutical Fabric Prevents COVID-19 Spread through Expelled Respiratory Droplets: A Combined Computational, Spectroscopic, and Antimicrobial Study.

Centers for Disease Control and Prevention (CDC) warns the use of one-way valves or vents in face masks for potential threat of spreading COVID-19 through expelled respiratory droplets. Here, we have developed a nanoceutical cotton fabric duly sensitized with non-toxic zinc oxide nanomaterial for potential use as a membrane filter in the one-way valve for the ease of breathing without the threat of COVID-19 spreading. A detailed computational study revealed that zinc oxide nanoflowers (ZnO NFs) with almost two-dimensional petals trap SARS-CoV-2 spike proteins, responsible to attach to ACE-2 receptors in human lung epithelial cells. The study also confirmed significant denaturation of the spike proteins on the ZnO surface, revealing removal of the virus upon efficient trapping. Following the computational study, we have synthesized ZnO NF on a cotton matrix using a hydrothermal-assisted strategy. Electron-microscopic, steady-state, and picosecond-resolved spectroscopic studies confirm attachment of ZnO NF to the cotton (i.e., cellulose) matrix at the atomic level to develop the nanoceutical fabric. A detailed antimicrobial assay using Pseudomonas aeruginosa bacteria (model SARS-CoV-2 mimic) reveals excellent antimicrobial efficiency of the developed nanoceutical fabric. To our understanding, the nanoceutical fabric used in the one-way valve of a face mask would be the choice to assure breathing comfort along with source control of COVID-19 infection. The developed nanosensitized cloth can also be used as an antibacterial/anti CoV-2 washable dress material in general.

Elastocaloric effect in zinc oxide nanowire

In this work, zinc oxide (ZnO) nanowire is proposed for elastocaloric application which has been overlooked until now. The elastocaloric effect ([Formula: see text]CE) is calculated by Maxwell relation. The large elastocaloric temperature and entropy change evaluated as 17 K and 28 J/kgK, respectively, at 300 K correspond to the stress of 12 GPa or strain of 5.5% by the simulation data. The elastocaloric temperature can be increased to 22 K under the operating tempering of 600 K. However, [Formula: see text]CE estimated from the experimental data is found as 2.6 K at 300 K, which corresponds to stress of 6 GPa. These results are expected to significantly expand the knowledge of ZnO nanomaterials as a potential candidate for [Formula: see text]CE. The results are based on the indirect approximation; hence, a direct measurement is needed to verify the obtained results.

Study on Ultraviolet Photodetector modified by Au Nanoparticles on ZnO Nanowires

Zinc oxide (ZnO) is a direct wideband gap semiconductor material with a band gap of 3.37eV at room temperature. It can absorb ultraviolet light with a wavelength shorter than 385nm and is light blind to visible light. Using different growth methods or different growth conditions, the final prepared ZnO nanomaterials have different growth structures, which can be presented as nano dots, nanowires, nanoribbons, nano rings, nano tubes and other structures. In this paper, the ultraviolet (UV) photodetector (PD) of ZnO nanowires (NWs) was first prepared by wet etching and hydrothermal method. Then, gold (Au) nanoparticles (NPs) was used as metal nanoparticles with surface modification to characterize the performance of the PD, and the study of NPs modification on the performance of the detector was explored. After testing, the NPs modification improved the responsivity by about 12 times and the absorption was also improved to a certain extent. This paper provides a valuable reference for the material selection of UV PDs based on ZnO NWs surface modification.

Synthesis of Zinc Oxide Nanomaterials via Sol-Gel Process with Anti-Corrosive Effect for Cu, Al and Zn Metallic Substrates

Nanosized zinc oxide (ZnO) particles modified with different silane coupling agents (octyltriethoxysilane (OTES), octadecyltriethoxysilane (ODTES) and (3-glycidyloxypropyl)trimethoxysilane (GPTMS)) were synthesized in basic catalysis using the sol-gel method. The structure and morphology were characterized by dynamic light scattering (DLS), environmental scanning electron microscopy (ESEM) and Fourier transform infrared spectroscopy (FTIR) for bonding characteristics. The final hybrid materials were deposited on three types of metallic substrates (aluminum (Al), copper (Cu) and zinc (Zn)) in order to obtain coatings with ultrahydrophobic and anti-corrosion properties. Water wettability was studied revealing a contact angle of 145° for the surface covered with ZnO material modified with ODTES. The water contact angle increased with the length of the alkyl chain supplied by the silica precursor. The anti-corrosive behavior of ZnO/silane coupling agents particles deposited on metallic substrates was studied by the linear polarization technique in neutral medium.

Biosynthesis of Zinc Oxide Nanomaterials from Plant Extracts and Future Green Prospects: A Topical Review

AbstractThis paper conducts a survey of the synthesis of zinc oxide nanomaterials using bio‐ and green‐ approaches that have attracted researchers’ attention. Compared to the traditional physical and chemical synthesis, the green method of biosynthesis stands out and has become a favorite route in the research field as it conforms to the sustainable development of modern society. The biosynthesis process of ZnO nanomaterials is mainly divided into two parts: one is the pretreatment of plant components; the other is the dissolving of plant extracts in zinc precursor solution to form ZnO nanomaterials. During this process, the precursor that provides the zinc source is reduced to precipitate zinc oxide. As a routine confirmatory test, a series of characterization techniques are conducted, and the results show that the synthesized zinc oxide nanomaterials can exhibit good antibacterial, photocatalytic, anti‐oxidant, and anti‐cancer properties. In addition, prominent trends and pivotal points in visualized networks of bioinspired zinc oxide are further verified and discussed in this work. An outlook for challenges and future studies is also provided.

Study of the Influence of Morphology, Chemical and Phase Compositions of Zinc Oxide-Containing Silicon and Titanium Oxide Nanomaterials on Cytotoxic Activity

The pulsed plasma-chemical method was used to obtain zinc oxide-contthe morphology and histograms of the particle aining silicon and titanium oxide nanocomposites (ZnOx-SiO2 and ZnOx-TiO2). To realize the method, a TEA-500 pulsed electron accelerator (Tomsk, Russia) was used. Zinc oxide (ZnO) nanopowder was obtained using the electrospark method. The morphology and phase composition of the synthesized nanopowders were determined using transmission electron microscopy (TEM) and X-ray diffraction (XRD) methods. The cytotoxicity of ZnO, ZnOx-SiO2, and ZnOx-TiO2 nanomaterials on HepG2 and 3T3-L1 adhesive cell lines was studied using thiazolyl blue tetrazolium bromide (MTT; Sigma). It was found that the size of the synthesized particles was in the range of 40–150 nm. The phase composition of ZnO, ZnOx-SiO2, and ZnOx-TiO2 nanomaterials was presented by several crystal structures. The dominant crystal lattice was ZnO with a hexagonal lattice for the ZnO sample, Zn (hexagonal lattice) for the ZnOx-SiO2 sample, and anatase for the ZnOx-TiO2 sample. The morphology of the ZnO, ZnOx-SiO2, and ZnOx-TiO2 nanoparticles was diverse. The cytotoxicity of ZnOx-SiO2 composite nanomaterials was much lower than that of the ZnO nanoparticles. The effect of increasing the viability of cells under the influence of low doses of ZnOx-TiO2 composite nanomaterials was revealed. These research results may present useful information for specialists involved in the development and application of functional nanocomposites.

Vermiwash-derived enzyme-activated ZnO nanomaterial towards two cascading applications: enhanced photocatalysis and effective irrigation

This study focuses on the preparation of enzyme-activated zinc oxide nanomaterial using vermiwash via a simple soft chemical method. This vermiwash––an aqueous extract obtained from vermin reactor––is produced using earthworm, Eudrilus eugeniae, cow dung and leaf litter. The prepared nanoproduct was used to decompose toxic dye molecules through photocatalysis. The enzymes present in the vermiwash (like amylase, phosphatase, urease and protease) are found to be inherited by the prepared nanoproduct as well as the photocatalytically treated water. The quantitative study of enzymes shows that the quantity of enzymes present in the nanoproduct as well as in the photocatalytically treated water increases as the proportion of vermiwash used in the starting solution increases. This increase in the quantity of enzymes causes an increase in the photocatalytic efficiency of the nanoproduct. The photocatalytically treated water which consists of enzymes can be used as a potential candidate for effective irrigation. Thus, the vermiwash-activated ZnO nanopowder prepared in this study shows a two linear cascading applications. The results of the studies on enzymes, photocatalysis, XRD, SEM and FTIR are appropriately correlated with one another to address the enhancement in the photocatalytic activity of the prepared nanomaterials and the underlying mechanism.

Multifunctional Oil Absorption with Macroporous Polystyrene Fibers Incorporating Silver-Doped ZnO

Hydrophobic microporous polystyrene (PS) fibers are fabricated by a solvent-induced phase-separation-assisted electrospinning method. Zinc oxide (ZnO) and silver-doped zinc oxide (Ag-ZnO) nanomaterials with variable morphologies are added to the PS fibers, to investigate the influence of multifunctional nanofiller addition on the porosity and consequent oil-adsorbing properties for different oil types. The doping of silver as well as the uniformity in particle distribution are confirmed by scanning electron microscopy and the energy-dispersive spectral analyses. The porosity of the fibers and their crystallinity effect depend on the hydrophobicity and surface properties of these microporous nanofilled fibers. Ag-ZnO, specifically in 2 wt %, enhanced the pore size and distribution in PS porous fibers, thereby enhancing the oil-adsorbing property and its hydrophobicity. In-depth analysis of the oil adsorption mechanism is done for the fibers, both qualitatively and quantitatively, to demonstrate its correlation with the structural integrity of the fibers. The PS/2Ag-ZnO composite also exhibits the highest antibacterial performance against Staphylococcus aureus, a general indication of antibiological fouling properties of these oil-separating films. The antifouling/antibacterial activity of the nanoparticles and high oil sorption capacity of the highly porous PS composites show great potential for use in water-treatment-related applications.

Single-step electrochemical synthesis of zinc oxide nanoflowers and multi-walled carbon nanotubes nanoconjugates

Zinc Oxide (ZnO) nanoparticles are investigated for use in various biomedical applications such as in the treatment of cancer because of their high targeting potential. Zinc oxide nanomaterials when conjugated with multi-walled carbon nanotubes (MWNT) show enhanced properties. In our present work, nano-conjugation between zinc oxide nanoflowers (ZnO NFs) and multi-walled carbon nanotubes has been successfully achieved. Here, we have used a two-electrode electrochemical setup for preparation as well as conjugation between ZnO nanoflowers and MWNT. The x-ray diffraction, Raman spectra, and transmission electron microscopy imaging for the ZnO NFs/MWNT nano-conjugate shows the successful synthesis of the nano-conjugate. The electrochemical method used here is a single step, economical, and without the use of any additional surfactant or capping agents. The only use of pure zinc electrodes as a precursor material favors high purity, easy and a less time-consuming purification process.

Green synthesis, characterization and antibacterial study on the catechin-functionalized ZnO nanoclusters

Green synthesis of zinc oxide nanomaterials has received recent attention due to the potential application of these nanomaterials as biocidal agents to combat antibiotic resistant organisms. In this paper, we provide a facile, one-step hydrothermal approach to prepare catechin-functionalized ZnO nanoclusters in aqueous solution. The obtained ZnO nanoclusters were characterized by UV spectroscopy (UV), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), atomic force microscopy (AFM), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS). The results of FTIR indicated that the catechin molecules were adsorbed on the surface of ZnO nanoclusters. TEM determination revealed that small ZnO nanoparticles tend to aggregate and form nanocluster structures. Antibacterial activity was tested by paper disk diffusion and the catechin-functionalized ZnO nanoclusters showed high biocidal activity against gram-positive bacteria, gram-negative bacteria and fungi.

Effect of synthetic route on morphology of zinc oxide and cadmium doped zinc oxide nanomaterials

In the current research, zinc oxide (ZnO) and cadmium doped ZnO nanoparticles (Cd-ZnO) were synthesized by hydrothermal and ultrasonication method utilising CTAB (cetyltrimethyl ammonium bromide), a cationic surfactant. The morphology and nature of crystal lattice of synthesized ZnO and Cd-ZnO nanoparticles were screened by SEM and XRD analysis. Effect of method of synthesis and dopant on the surface morphology of ZnO nanoparticles was studied. SEM studies showed the formation of ZnO nanorods (∼30–57 nm) through hydrothermal method, and nanograins (∼37–53 nm) via ultrasonication. For Cd-ZnO a vast difference was observed in the surface topography. Among the two mentioned methods Cd-ZnO nanoflakes were obtained by ultrasonication (∼100 nm) whereas hydrothermally derived Cd-ZnO was resulted as agglomerated nanorods of about 50 to 100 nm. XRD analysis also supported the results. Hence, it was shown that both the mode of synthesis has a significant effect and process of doping has a remarkable effect on the surface morphology of the ZnO nanoparticles.

Low-temperature synthesis of cadmium-doped zinc oxide nanosheets for enhanced sensing and environmental remediation applications

In the present study, we report the effect of Cd doping on the photocatalytic and photoluminescence properties of ZnO nanoparticles. Large scale synthesis of pure and Cd-doped zinc oxide (ZnO) nanoparticles was carried out by using the facile solution route at low temperature (60 °C). The synthesized products were characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) attached with energy dispersive spectroscopy (EDS), UV–visible and photoluminescence spectroscopy. The detailed analysis revealed that the synthesized nanostructures were pure and well crystalline in nature and possessed wurtzite hexagonal crystal phase. Further photocatalytic results revealed that almost complete degradation of Rhodamine B (RhB) dye (10 ppm) occurred by 0.05 g of the 10% Cd-doped ZnO nanostructure within 110 min of UV exposure. In contrast, for pure ZnO, only 50% degradation of dye occured under the same set of conditions. Moreover, the photocatalytic degradation efficiency was increased with increase in the concentration of Cd2+ ions as a dopant. The better photodegradation efficiency of samples with an increase in dopant concentration was attributed to increase in the defects and reduction in bandgap width of ZnO nanoparticles. As-synthesized material was also explored as an efficient chemical sensor for the detection of hydrazine. A comparative study revealed a sharp decrease in the limit of detection for hydrazine sensing with the increased concentration of Cd2+ ions as a dopant. The Cd-doped ZnO nanomaterial also showed enhanced magnetism as compared to pure ZnO nanoparticles.

Solar energy-controlled shape selective synthesis of zinc oxide nanomaterials and its catalytic application in synthesis of glycerol carbonate

In this study, we have synthesized shape selective zinc oxide (ZnO) nanoflower using solar energy and naturally accessible aromatic amino acids like tryptophan, tyrosine and phenylalanine as a photo capping agents. This synthesized material has been characterized by various characterization techniques such as XRD, FE-SEM, EDX, UV–Vis and FTIR. The ZnO nanoflower synthesized using solar energy and photo capping agents exhibited excellent catalytic activity after calcination for the synthesis of glycerol carbonate via urea glycerolysis as compared to the conventional process owing to its shape selective morphology. Further, high resolution XPS studies were performed to explore the valence states and effectiveness of surface engineering of the ZnO catalyst. Such a unique technique of ZnO nanoflowers synthesis represents a novel and environmentally benign route for synthesis of shape selective metal oxide nanoparticles as well as derived nanomaterial after calcination showed excellent activity and potential recyclability for the conversion of waste into valuable products. After calcination ZnO nanomaterials shows 67% yield in the synthesis of glycerol carbonate at 140 ​°C in 4 ​h, at the end a catalytic reaction mechanism was proposed.

Evaluation of toxicity of zinc oxide nanorods on green microalgae of freshwater and marine ecosystems

Zinc oxide (ZnO) nanomaterials (NMs) are widely used in the manufacture of several commercial products like foods, packaging, cosmetics, medicines and healthcare formulations and anti-fouling paints. These NMs can pollute water bodies when they become bioavailable. In this context, this study investigated the toxicity of ZnO nanorods (NRs) on green microalgae from freshwater and marine ecosystems, to better understand the behavior of this NM on each environment. Two green microalgae species, Desmodesmus subspicatus (freshwater) and Tetraselmus sp. (marine), were evaluated by chronic toxicity tests and oxidative stress induction by the enzymatic activity of catalase (CAT). The exposition assays were performed using three different concentrations of ZnO NRs (0.1, 1.0, and 10 mg/L, and a negative control). ZnO NRs significantly affected the growth rate of both tested chlorophytes. The chronic toxicity test showed LOEC (Lowest Observed Effect Concentration) levels of 10 mg/L (72 h) for D. subspicatus and 1.0 mg/L (24 h) for Tetraselmis sp. It was observed NOEC (No Observed Effect Concentration) levels of 1.0 mg/L to D. subspicatus was (at 72 h) and of <0.1 mg/L for Tetraselmis sp . (at 24 h). In the enzymatic activity tests of D. subspicatus exposed to ZnO NRs, the CAT activity caused significant changes at the concentration at 10 mg/Lof ZnO NRs when compared to the control test, but for Tetraselmis sp. no change was observed in CAT activity. These results indicate that D. subspicatus was more sensitive to the effects of ZnO NRs at the concentration of 10 mg/L after 72 h, while oxidative stress of this alga was also observed at the same concentration. The results of this study show the importance of further investigating the toxicological effects of ZnO NRs on green microalgae from distinct aquatic environments and of evaluating the toxicological response of these microalgae in culture media. • Ecotoxicity of zinc oxide nanorods (ZnO NR) was evaluated on freshwater and marine green microalgae. • Freshwater microalgae showed more sensitivity than marine microalgae to ZnO NR. • ZnO NR induced oxidative stress in freshwater microalgae, evidenced by a change in CAT activity. • The response to ZnO NR toxicity is affected by the nature of the organism and its ecosystem.