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K. Gwóźdź, E. Płaczek-Popko, Z. Gumienny, E. Zielony, R. Pietruszka, B. S. Witkowski, Ł. Wachnicki, S. Gierałtowska, M. Godlewski and L. B. Chang

. Wu, Y. Lu, H. He, J. Huang, B. Zhao and Z. Ye, “Enhanced near band edge emission of ZnO via surface plasmon resonance of aluminum nanoparticles”, Journal of Applied Physics , 110, 023510 (2011). [10] J.H. Parker, D.W. Feldman and M. Ashkin, “Raman scattering by silicon and germanium”, Physical Review , 155, 712–714 (1967). [11] R. Cuscó, E. Alarcón-Lladó, J. Ibáñez, L. Artús, J. Jiménez, B. Wang and M.J. Callahan, “Temperature dependence of Raman scattering in ZnO”, Physical Review B: Condensed Matter and Materials Physics , 75, 165202 (2007

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Raminder Preet Pal Singh, I.S. Hudiara and Shashi Bhushan Rana

nanostructures. Therefore, not only various synthesis methods but also the physical and chemical properties of synthesized zinc oxide are to be studied with respect to its morphology [ 3 ]. Diluted magnetic semiconductors (DMS) have attracted much attention in recent years because they are the type of semiconductor in which fraction of host cations can be easily replaced by magnetic ions in fabrication of spintronics devices, such as spin valve transistor [ 4 – 7 ]. In the past few years, scientists have investigated the effect of ZnO nanoparticles doping with transition

Open access

A. Roguska, A. Belcarz, P. Suchecki, M. Andrzejczuk and M. Lewandowska

Abstract

Problem of post-operative infections of implant materials caused by bacterial adhesion to their surfaces is very serious. Enhancement of antibacterial properties is potentially beneficial for biomaterials value. Therefore, the metallic and metallic oxide nanoparticles attract particular attention as antimicrobial factors. The aim of this work was to create nanotubular (NT) oxide layers on Ti with the addition of ZnO nanoparticles, designed for antibacterial biomedical coatings. Antimicrobial activities of titanium, TiO2 NT and ZnO/TiO2 NT surfaces were evaluated against bacterial strain typical for orthopaedic infections: S. epidermidis. TiO2 NT alone killed the free bacterial cells significantly but promoted their adhesion to the surfaces. The presence of moderate amount of ZnO nanoparticles significantly reduced the S. epidermidis cells adhesion and viability of bacterial cells in contact with modified surfaces. However, higher amount of loaded nanoZnO showed the reduced antimicrobial properties than the medium amount, suggesting the overdose effect.

Open access

A. Roguska, A. Belcarz, P. Suchecki, M. Andrzejczuk and M. Lewandowska

Problem of Post-operative infections of implant materials caused by bacterial adhesion to their surfaces is very serious. Enhancement of antibacterial properties is potentially beneficial for biomaterials value. Therefore, the metallic and metallic oxide nanoparticles attract particular attention as antimicrobial factors. The aim of this work was to create nanotubular (NT) oxide layers on Ti with the addition of ZnO nanoparticles, designed for antibacterial biomedical coatings. Antimicrobial activities of titanium, TiO2 NT and ZnO/TiO2 NT surfaces were evaluated against bacterial strain typical for orthopaedic infections: S. epidermidis. TiO2 NT alone killed the free bacterial cells significantly but promoted their adhesion to the surfaces. The presence of moderate amount of ZnO nanoparticles significantly reduced the S. epidermidis cells adhesion and viability of bacterial cells in contact with modified surfaces. However, higher amount of loaded nanoZnO showed the reduced antimicrobial properties than the medium amount, suggesting the overdose effect.

Open access

P. Maddahi, N. Shahtahmasebi, A. Kompany, M. Mashreghi, S. Safaee and F. Roozban

. http://dx.doi.org/10.2109/jcersj.108.1254_156 [12] Fernandes D.M., Silva R., Winkler Hechenleitner A.A., Radovanovic E., Custódio Melo M.A., Gómez Pineda E.A., “Synthesis and characterization of ZnO, CuO and a mixed Zn and Cu oxide”, Mater. Chem. Phys., 115 (2009), 110. http://dx.doi.org/10.1016/j.matchemphys.2008.11.038 [13] Bian J., Lou Y., Sun J., Liang H., Liu W., J. Mater. Process. Tech., 189 (2007), 473. http://dx.doi.org/10.1016/j.jmatprotec.2007.02.021 [14] Gayen R.N., Das S

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Nashiruddin Ahammed, Md Samim Hassan and Mehedi Hassan

Abstract

In this research article, pure and 1 %, 3 % and 5 % aluminium doped zinc oxide nanoparticles (NPs) were prepared via sol-gel method and then calcined at 500 °C. X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectroscopy, UV-Vis spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques were used to investigate the structural, optical and thermal properties of synthesized pure and Al doped ZnO nanoparticles. Energy dispersive X-ray spectroscopy (EDX) analysis revealed high purity of nanoparticles in the synthesized products without any impurity peaks. Mean dimension of the nanoparticles was ~28 nm and they were hexagonal in shape, according to the images analyzed by transmission electron microscope (TEM). The optical absorption spectra of pure and Al doped ZnO samples studied using UV-Vis spectrometry have been presented and we have observed that the band gap increases with increasing Al concentration. In FT-IR spectra, the broad absorption peaks around 485 cm−1 and 670 cm−1 were assigned to Zn–O vibration. Above 450 °C, the TG curve became flat what means there was no weight loss. In the DSC curve it is seen that the transition at 150 °C was highly exothermic because of structural relaxation and on doping the exothermic peaks became shifted to the lower value of temperature. These types of materials are very useful in optoelectronics applications.

Open access

B. Stypuła, M. Starowicz, M. Hajos and E. Olejnik

Electrochemical Synthesis of ZnO Nanoparticles During Anodic Dissolution of Zinc in Alcohols Solvents

Studies of the effect of the kind of alcohol, electrolyte concentration and water on the anodic dissolution of zinc and the nature of dissolution products were performed. The dissolution products were analyzed by spectroscopic methods (SEM/EDS, XPS and UV-vis) and X-ray diffraction. These studies have shown that the process of anodic dissolution of zinc in alcohol electrolytes (methanol and ethanol) in the presence of water (1-5% vol.), is a simple way to obtain ZnO nanoparticles.

Open access

B. Hutera, A. Kmita, E. Olejnik and T. Tokarski

The paper presents a method for obtaining nanoparticles of ZnO by thermal decomposition of the Zn-containing compounds. The experiment was based on the thermal decomposition of basic zinc carbonate to zinc oxide (with a content of 58-61 wt.%). Basic zinc carbonate was analysed by derivatography and then annealed at a selected temperature (about 600ºC) for about 1 h. Products of thermal decomposition of the compound were studied by XRD analysis and SEM scanning microscopy.

Open access

Abdelali Merah, Abdenabi Abidi, Hana Merad, Noureddine Gherraf, Mostepha Iezid and Abdelghani Djahoudi

References [1] Hench, L.L.; West, J.K., The sol-gel process, Chem. Rev ., 1990 , 90 , 33-72 [2] Wright, J. D.; Sommerdijk, N. A. J. M., Sol-gel materials: chemistry and applications. Advanced chemistry texts , 2001 , 4 . Amsterdam: Gordon and Breach Science Publishers. [3] Brinker, C. J.; Scherer, G. W., Sol-Gel Science: Physics and Chemistry of Sol-Gel Processing Academic Press , 1990 [4]. Nejati, A.; Rezvani, Z.; Pakizev, R., Synthesis of ZnO Nanoparticles and Investigation of the Ionic Template Effect on Their Size and Shape

Open access

Madiha Sarfraz, Nasar Ahmed, Khizar-ul-Haq, Shabnam Shahida and M. A. Khan

Abstract

Transition metals, such as chromium (Cr) and manganese (Mn) doped zinc oxide (ZnO) magnetic nanoparticles, were synthesized via sole gel auto-combustion method. The prepared magnetic (Zn1−(x+y)MnxCryO, where x, y = 0, 0.02, 0.075) nanoparticles were calcined in an oven at 6000 °C for 2 hours. The morphologies of the nanoparticles were investigated using different techniques. X-ray diffraction (XRD) analysis revealed that the hexagonal wurtzite structure of the synthesized nanoparticles was unaffected by doping concentration. The crystallite size measured by Scherrer formula was in the range of 32 nm to 38 nm at different doping concentrations. Nanosized particles with well-defined boundaries were observed using a field emission scanning electron microscopy (FE-SEM). Fourier transform infrared (FT-IR) spectra showed a wide absorption band around 1589 cm−1 in all the samples, corresponding to the stretching vibration of zinc and oxygen Zn–O bond. A blue shift in optical band gaps from 3.20 eV for ZnO to 3.08 eV for Zn0:85Mn0:075Cr0:075O nanoparticles was observed in diffuse reflectance spectra, which was attributed to the sp-d exchange interactions. The field-dependent magnetization M-H loops were measured using vibrating sample magnetometer (VSM). The VSM results revealed diamagnetic behavior of the ZnO nanoparticles which changed into ferromagnetic, depending on the doping concentration and particle size. The compositions of Zn, Cr, Mn and O in the prepared samples were confirmed by using the energy dispersive X-ray spectroscopy (EDX). Our results provided an interesting route to improve magnetic properties of ZnO nanoparticles, which may get significant attention for the fabrication of magnetic semiconductors.