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1.
Synthesis of pure Zinc oxide (ZnO), Copper oxide (CuO) nanoparticles (NPs) and their (ZnO/CuO) nanocomposites (NCs) in 1:1 M ratio were successfully prepared by co-precipitation method. The structural properties of the as synthesized nanoparticles and nanocomposite materials were investigated using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) techniques. Optical band-gap studies were done using UV–Visible absorption spectroscopy. Photovoltaic properties of pure ZnO NPs, CuO NPs and ZnO/CuO NCs coated over a single-crystalline silicon solar cell were carried out to compare improvement of light-conversion efficiency in coated solar cell. The maximum light conversion efficiencies were found to be of 8.02% for CuO (3 mg/ml concentration) and 7.28% for ZnO NPs (3 mg/ml concentration), whereas that of mixed metal nanocomposite CuO/ZnO NCs was found to be 7.62%. at very low concentration of 1 mg/ml. This indicates with low concentration of mixed metal NCs an improvement in light efficiency can be obtained. The enhancement in efficiency could be due to formation of p - n heterojunction by CuO/ZnO NCs composites which enhances the number of electrons and holes participating in conduction on the surface.  相似文献   

2.
The toxic dye pigments, even in small quantities, can damage ecosystems. Removing organic, inorganic, and microbiological contaminants from wastewater via heterogeneous photocatalysis is a promising method. Herein, we report the band structure tuning of ZnO/CuO nanocomposites to enhance photocatalytic activity. The nanocomposites were synthesized by a chemical approach using step-wise implantation of p-type semiconductor CuO to n-type semiconductor ZnO. Various characterization techniques such as X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDX) and UV spectroscopy were used to investigate the crystal structure, surface morphology, elemental composition and optical properties of the synthesized samples. As the CuO content increased from 10% to 50% in ZnO/CuO nanocomposites, the optical bandgap decreased from 3.36 to 2.14 eV. The photocatalytic activity of the samples was evaluated against the degradation of methylene blue (MB) under visible irradiation. Our study demonstrates a novel p–n junction oxide photocatalyst based on wt. 10% CuO/ZnO with superior photocatalytic activity. Effectively 66.6% increase in degradation rate was achieved for wt. 10% CuO/ZnO nanocomposite compared to pure ZnO nanoparticles.  相似文献   

3.
Magnetite zinc oxide (MZ) (Fe3O4/ZnO) with different ratios of reduced graphene oxide (rGO) was synthesized using the solid-state method. The structural and optical properties of the nanocomposites were analyzed using transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis/DRS), and photoluminescence (PL) spectrophotometry. In particular, the analyses show higher photocatalytic movement for crystalline nanocomposite (MZG) than MZ and ZnO nanoparticles. The photocatalytic degradation of methylene blue (MB) with crystalline ZnO for 1.5 h under visible light was 12%. By contrast, the photocatalytic activity for MZG was more than 98.5%. The superior photocatalytic activity of the crystalline nanocomposite was detected to be due to the synergistic effect between magnetite and zinc oxide in the presence of reduced graphene oxide. Moreover, the fabricated nanocomposite had high electron–hole stability. The crystalline nanocomposite was stable when the material was used several times.  相似文献   

4.
The disinfection of wastewater using nanoparticles (NPs) has become a focal area of research in water treatment. In this study, zinc oxide (ZnO) NPs were synthesized using the microwave heating crystallization technique and characterized using transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). Qualitative well diffusion and quantitative minimum inhibitory concentration (MIC) tests were conducted to determine the antimicrobial activity of ZnO NPs against selected waterborne pathogenic microbes. FTIR spectral studies confirmed that the binding of urea with Zn occurs through Zn–O stretching. XRD confirmed the crystallized identity in a hexagonal ZnO wurtzite-type structure. The formation of zones of inhibition and low MIC values in the antimicrobial analysis were indicative of the effective antimicrobial activity of zinc oxide nanoparticles against the test microorganisms. The application of metallic nanoparticles in water treatment could curb the spread of waterborne microbial diseases.  相似文献   

5.
In the present investigation, novel poly(amid-imide)/zinc oxide nanocomposites (PAI/ZnO NCs) containing benzoxazole and benzimidazole pendent groups with different amounts of modified zinc oxide nanoparticles (ZnO NPs) were successfully prepared via the ex situ method. Poly(amid-imide) (PAI) was prepared by direct polycondensation of 2-[3,5- bis(N-trimellitimidoyl)phenyl]benzoxazole (DCA) with 5-(2-benzimidazole)-1,3-phenylenediamine (DAMI) and provided the polymeric matrix with well-designed groups. The surface of ZnO NPs was functionalized with 3-aminopropyltriethoxysilane (APS) coupling agent to have a better dispersion and enhancing possible interactions of NPs with functional groups of polymer matrix. The amount of APS bonded to the ZnO surface was determined by thermogravimetric analysis. PAI/ZnO nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). SEM analysis showed that the modified ZnO nanoparticles were homogeneously dispersed in polymer matrix. In addition, TGA data indicated an enhancement of thermal stability of the nanocomposite compared with the neat polymer.  相似文献   

6.
In the present study, montmorillonite (MMT) nanoclay and copper oxide (CuO) nanoparticles (NPs) reinforced polyvinylchloride (PVC) based flexible nanocomposite films were prepared via solvent casting technique. Using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and thermo-gravimetric analysis (TGA), the structural, morphological and thermal properties of PVC/MMT/CuO nanocomposite films with various loadings of CuO NPs and MMT were investigated. These studies suggested that by the addition of dual nanofillers in the polymer matrix some structural modifications occurred owing to the homogenous dispersion of MMT and CuO NPs within the PVC matrix. The TGA results reveal that the addition of CuO NPs and MMT considerably improved the thermal stability of the nanocomposites. The EMI shielding effectiveness (SE) of nanocomposites was examined in the X-band (8–12 GHz) and Ku-band (12–18 GHz) frequency regions. The EMI SE values were found to be −30 dB (X-band) and −35 dB (Ku-band) for nanocomposites containing 0.3 wt% of CuO NPs and 4.7 wt% of MMT respectively while the shielding was found to be absorption dominant. These results emphasize that PVC/MMT/CuO nanocomposite films can be used as a potential EMI shielding material.  相似文献   

7.
Syntheses of zince oxide(ZnO) nanoparticles by direct precipitation and surface modification with oleic acid were reported. ZnO nanoparticles were characterized via X-ray diffractometry(XRD), transmission electron microscopy(TEM), infrared spectroscopy(IR) and UV-Vis spectroscopy. The prepared ZnO nanoparticles were nearly spherical and highly crystalline with an average size of 29 nm. In addition, high UV-light absorption properties of oleic acid surface modified ZnO nanoparticles were successfully obtaine...  相似文献   

8.
ZnO nanoparticles(NPs)with different contents of Ag dopants were obtained by one-step solvothermal method.The crystalline structures of the prepared composites were characterized by means of X-ray diffraction(XRD).The morphology and composition of the samples were studied by means of scanning transmission electron microscopy(TEM)5 X-ray photoelectron spectroscopy(XPS)and electron microscopy(SEM).Photoluminescence(PL)spectra have been used to investigate pure ZnO,Ag-ZnO and Ag-ZnO-PVP NPs to determine the effect of composition on PL properties.It was found that the Ag-ZnO samples showed stronger emissions than pure ZnO.The catalytic activity of samples was measured by the degradation rate of R6G,which exhibited that Ag-ZnO nanocomposite demonstrated enhanced photocatalytic activity compared to the pure ZnO NPs.The possible influence factors to the photocatalytic and antibacterial activities of the sample were explored,including Ag contents and dispersion.It was presented that the photocatalytic activity of Ag-ZnO-PVP was better than that of Ag-ZnO and it showed the highest photocatalytic activity with 7%of Ag content.The Ag-ZnO-PVP can kill the Escherichia coli(E.coli)cells.  相似文献   

9.
Advanced innovations for combating variants of aggressive breast cancer and overcoming drug resistance are desired. In cancer treatment, ZnO nanoparticles (NPs) have the capacity to specifically and compellingly activate apoptosis of cancer cells. There is also a pressing need to develop innovative anti-cancer therapeutics, and recent research suggests that ZnO nanoparticles hold great potential. Here, the in vitro chemical effectiveness of ZnO NPs has been tested. Zinc oxide (ZnO) nanoparticles were synthesized using Citrullus colocynthis (L.) Schrad by green methods approach. The generated ZnO was observed to have a hexagonal wurtzite crystal arrangement. The generated nanomaterials were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV-visible spectroscopy. The crystallinity of ZnO was reported to be in the range 50–60 nm. The NPs morphology showed a strong absorbance at 374 nm with an estimated gap band of 3.20 eV to 3.32 eV. Microscopy analysis proved the morphology and distribution of the generated nanoparticles to be around 50 nm, with the elemental studies showing the elemental composition of ZnO and further confirming the purity of ZnO NPs. The cytotoxic effect of ZnO NPs was evaluated against wild-type and doxorubicin-resistant MCF-7 and MDA-MB-231 breast cancer cell lines. The results showed the ability of ZnO NPs to inhibit the prefoliation of MCF-7 and MDA-MB-231 prefoliation through the induction of apoptosis without significant differences in both wild-type and resistance to doxorubicin.  相似文献   

10.
The present research highlights physical significance of green combination of metal oxide nanomaterials utilizing medicinal plant which has widely analyzed in different medical applications i.e., medicinal science, therapeutics. In this paper, we discussed environmentally benign approach for synthesizing silver doped copper oxide nanoparticles (Ag–CuO NPs) utilizing (ACLE). Scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) were utilized to confirm the size, crystalline structure and surface morphology of the obtained nanomaterials. The monoclinic crystalline structure of the Ag–CuO NPs as produced was revealed by XRD patterns. Morphological analysis disclosed the nano-based spherical configuration of Ag–CuO NPs, as well as their morphology and elemental composition. The anti-diabetic effect of Ag–CuO NPs was further investigated utilizing a yeast cell model and amylase inhibition. Here, a decrease in intracellular glucose and a delay in carbohydrate digestion indicate promising antidiabetic action. Furthermore, the prepared nanomaterial showed anticancer potential against the MCF-7 cancer cell line, with an IC 50 value of 11.21 g/ml.  相似文献   

11.
In this work, the assessment of Azadirachta indica, Tagetes erecta, Chrysanthemum morifolium, and Lentinula edodes extracts as catalysts for the green synthesis of zinc oxide nanoparticles (ZnO NPs) was performed. The photocatalytic properties of ZnO NPs were investigated by the photodegradation of methylene blue (MB) dye under sunlight irradiation. UV-visible (UV-Vis) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), Thermogravimetric (TGA), and Brunauer-Emmett-Teller analysis (BET) were used for the characterization of samples. The XRD results indicate that all synthesized nanoparticles have a hexagonal wurtzite crystalline structure, which was confirmed by TEM. Further, TEM analysis proved the formation of spherical and hemispherical nanoparticles of ZnO with a size in the range of 14–32 nm, which were found in aggregate shape; such a size was well below the size of the particles synthesized with no extract (~43 nm). ZnO NPs produced with Tagetes erecta and Lentinula edodes showed the best photocatalytic activity, matching with the maximum adsorbed MB molecules (45.41 and 58.73%, respectively). MB was completely degraded in 45 min using Tagetes erecta and 120 min using Lentinula edodes when subjected to solar irradiation.  相似文献   

12.
采用静电纺丝技术及煅烧法制备了氧化锌纳米纤维, 然后采用水热法将银纳米颗粒负载到了氧化锌纳米纤维表面. 利用X射线衍射(XRD)、 X射线光电子能谱(XPS)、 能量色散X射线光谱(EDX)、 扫描电子显微镜(SEM)及透射电子显微镜(TEM)等技术对合成的Ag/ZnO纳米纤维的结构和组成进行了表征. SEM结果表明, 直径在5~100 nm之间的银纳米颗粒附着在直径在80~330 nm之间的氧化锌纤维表面形成了异质结构. 以常见的有机污染物甲基橙、 亚甲基蓝和罗丹明B等为降解底物, 对Ag/ZnO纳米纤维的光催化性能进行了表征. 结果表明, 负载银纳米颗粒后, 复合催化剂的光催化性能明显提高.  相似文献   

13.
In the present study copper oxide nanoparticles (CuO NPs) were synthesized using a hydrothermal method with ranolazine as a shape-directing agent. Ranolazine-functionalized CuO NPs were characterized by various analytical techniques such as scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The SEM pattern confirmed the morphology of ranolazine-functionalized CuO NPs with well-defined rice-like structures. FTIR spectroscopy confirmed the interaction between CuO NPs and ranolazine. The XRD analysis indicated that the structure of ranolazine-functionalized CuO NPs was monoclinic crystalline and the size ranged between 9 and 18 nm with an average particle size of 12 nm. The smaller size range of CuO NPs gave a large surface area that enhanced the efficiency of these catalysts employed for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the H 2 O system. In homogeneous catalysis, results showed that 50 μL of CuO NPs was required in the presence of NaBH4 for 99% reduction of 4-NP in 240 s. On the other hand, for heterogeneous catalysis, 0.5 mg of CuO NPs was used in the presence of NaBH4 for 99% catalytic reduction of 4-NP to 4-AP in 320 s. The rate of reaction for homogeneous catalysis and heterogeneous catalysis was determined from the plots of In(Ct /C0) of 4-NP versus time (s), which showed good linearity with values of 1.3 × 10 -2 and 8.8 × 10 -3 s -1 . respectively. The high-quality catalytic efficiency, good reusability, nontoxic nature, and low cost are favorable properties of the synthesized CuO NPs for use as efficient catalysts for reduction of 4-AP to 4-NP in both homogeneous and heterogeneous media.  相似文献   

14.
Plant-based nanoparticles (NPs) have found great interest among various scientist in the present era and used in various sector including medicine, agriculture, and food industry. The various chemical constituents of plants aid in the bioreduction of metal ions to a nanoscale. Among the various NPs synthesized, zinc oxide (ZnO) NPs hold a premier position. ZnO NPs have use in textile, cosmetic, diagnostics, optoelectronics, photocatalysis, diodes, and many other areas. NPs synthesized through green synthesis have a potentially greater role in treating clinical pathogens. Present investigations show a simple eco-friendly method for the synthesis of ZnO NPs from the husk of sunflower seeds. Sunflower is an economically important crop, for the formation of edible oil. The husk is considered to be a waste, product in oil industry, however, the biomolecules present in sunflower husk can be used to produce ZnO NPs. Present investigations reveal formation of ZnO NPs and investigations of their structure through scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Their optical properties have been studied by ultraviolet–visible spectrophotometer (UV–Vis) and fluorophotometer. ZnO NPs have also been investigated for their potential phytoremedial properties.  相似文献   

15.
Zinc oxide@carbon quantum dots (ZnO@CQDs) nanocomposite was prepared via a facile hydrothermal method. Characterization of the obtained samples was carried out by Scanning electron microscopy-EDX(SEM–EDX), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Photoluminescence (PL), and Fourier transformed infrared spectroscopy (FT-IR). These results revealed that we have prepared ZnO@CQDs nanocomposite successfully. Our study revealed that the antibacterial efficiency (against S.aureus and E.coli) under visible light irradiation of as prepared ZnO@CQDs nanocomposite was higher than pure ZnO nanoparticles. The ZnO@CQDs nanocomposite showed excellent antibacterial activity against Gram-negative and Gram-positive bacteria with a minimal inhibitory concentration (6–8 mg/mL) against to E.coli and S.aureus. We also tested the light response of ZnO@CQDs under UV–vis light, by calculating its band gap data, after decorated with CQDs, the band gap of the pure ZnO can significantly decreased from 2.57 eV to 2.50 eV. The ZnO decorated by CQDs can both enhance the light absorption and suppress photogenerated electron–hole's recombination which results in the enhancement of antibacterial properties.  相似文献   

16.
Ternary Ag/Polyaniline/Au nanocomposites were synthesized successfully by immobilizing of Au nanoparticles (NPs) on the surface of Ag/Polyaniline (PANI) nanocomposites. Ag/PANI nanocomposites were prepared via in situ chemical polymerization of aniline in the presence of 4-aminothiophenol (4-ATP) capped silver colloidal NPs. Then, uniform gold (Au) NPs were assembled on the surface of resulted Ag/PANI nanocomposites through electrostatic interaction to get Ag/Polyaniline/Au nanocomposites. The nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), ultraviolet visible spectroscopy (UV-Vis), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). Moreover, Ag/PANI/Au nanocomposites were immobilized on the surface of a glassy carbon electrode and showed enhanced electrocatalytic activity for the reduction of H2O2 compared with Ag/PANI.  相似文献   

17.
Nowadays, the industrial wastewater pollutants including toxic dyes and pathogenic microbes have caused serious environmental contaminations and human health problems. In the present study, eco-friendly and facile green synthesis of Ag modified ZnO nanoparticles (ZnO-Ag NPs) using Crataegus monogyna (C. monogyna) extract (ZnO-Ag@CME NPs) is reported. The morphology and structure of the as-biosynthesized product were characterized by field emission scanning electron microscopy (FESEM), X-Ray diffraction (XRD), differential reflectance spectroscopy (DRS), dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and energy-dispersive X-ray spectroscopy (EDS) techniques. TEM and FESEM images confirmed the oval and spherical-like structure of the products with a size of 55–70 nm. The EDS analysis confirmed the presence of Zn, Ag, and O elements in the biosynthesized product. The photocatalytic results showed ZnO-Ag@CME NPs were degraded (89.8% and 75.3%) and (94.2% and 84.7%) of methyl orange (MO) and basic violet 10 (BV10), under UV and sunlight irradiations, respectively. The Ag modified ZnO nanoparticles exhibited enhanced catalytic activity towards organic pollutants, and showed better performance than the pure ZnO nanoparticles under UV and sunlight irradiations. This performance was probably due to the presence of silver nanoparticles as a plasmonic material. Antibacterial activity was performed against different bacteria. ZnO-Ag@CME NPs showed high antibacterial activity against K. pneumoniae, S. typhimurium, P. vulgaris, S. mitis, and S. faecalis with MIC values of 50, 12.5, 12.5, 12.5, and 12.45 µg/mL, respectively. All in all, the present investigation suggests a promising method to achieve high-efficiency antibacterial and catalytic performance.  相似文献   

18.
Fiber-shaped cupric oxide (CuO) nanoparticles and flower-shaped ZnO nanoparticles were facilely synthesized by plasma-induced technique directly from copper and zinc electrode pair in water, respectively. The phase composition, morphologies and optical property of nanoparticles have been investigated by energy dispersive X-ray analysis, X-ray powder diffraction, transmission electron microscopy and UV–vis. The in situ analysis by an optical emission spectroscopy clarified the formation mechanism. Plasma was generated from the discharge between a metal electrode pair in water by a pulse direct current power. CuO and ZnO nanoparticles were synthesized via almost the same formation mechanism, which were prepared via the rapid energetic radicals’ bombardment to electrodes’ surface, atom vapour diffusion, plasma expansion, solution medium condensation, and in situ oxygen reaction and further growth. This novel plasma-induced technique will become a potential application in nanomaterials synthesis.  相似文献   

19.
Epilepsy is a neurological disorder involving persistent spontaneous seizures and uncontrolled neuronal excitability that leads to cognitive impairments and blood–brain barrier (BBB) disruption. Currently available antiepileptic drugs present side effects and researchers are trying to discover new agents with properties to overcome these drawbacks. The aim was to synthesize magnesium oxide (MgO) and zinc oxide (ZnO) nanoparticles from Datura alba fresh leaf extracts and evaluate their anti-epileptic potential in mice kindling or a repetitive seizures model. The phytoassisted synthesized nanoparticles were characterized using spectroscopy; FT-IR, XRD, SEM, and EDX. Analysis of the NPs confirmed the crystalline pleomorphic shape using the salts of both zinc and magnesium possibly stabilized, functionalized and reduced by bioactive molecules present in plant extract. By using several characterization techniques, NPs were confirmed. UV-Vis spectroscopy of biologically produced ZnO and MgO revealed distinctive peaks at 380 nm and 242 nm, respectively. Our findings categorically demonstrated the reductive role of biomolecules in the formation of ZnO and MgO NPs. The mice kindling model was induced using seven injections of Pentylenetetrazole (PTZ, 40 mg/kg, i.p) for 15 days alternatively. The results showed that mice post-treated with either ZnO or MgO nanoparticles (10 mg/kg, i.p) significantly improved in respect of behavior and memory as confirmed in the Morris water maze (MWM), open field (OF), novel object recognition (NOR) test compared with PTZ treated mice. Furthermore, the ZnO and MgO nanoparticle treatment also maintained the integrity of the BBB, reducing the leakage, as confirmed by Evans blue dye (EBD) compared with PTZ treated mice only. In summary, the current finding demonstrates that green synthesized ZnO and MgO nanoparticles have neuroprotective, ant-epileptic potential, molecular mechanisms, and clinical implications need to be further explored.  相似文献   

20.
In the present work, the properties of ZnO nanoparticles obtained using an eco-friendly synthesis (biomediated methods in microwave irradiation) were studied. Saponaria officinalis extracts were used as both reducing and capping agents in the green nanochemistry synthesis of ZnO. Inorganic zinc oxide nanopowders were successfully prepared by a modified hydrothermal method and plant extract-mediated method. The influence of microwave irradiation was studied in both cases. The size, composition, crystallinity and morphology of inorganic nanoparticles (NPs) were investigated using dynamic light scattering (DLS), powder X-ray diffraction (XRD), SEM-EDX microscopy. Tunings of the nanochemistry reaction conditions (Zn precursor, structuring agent), ZnO NPs with various shapes were obtained, from quasi-spherical to flower-like. The optical properties and photocatalytic activity (degradation of methylene blue as model compound) were also investigated. ZnO nanopowders’ antibacterial activity was tested against Gram-positive and Gram-negative bacterial strains to evidence the influence of the vegetal extract-mediated synthesis on the biological activity.  相似文献   

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