ano structure via Sol-Gel and Precipitation Chemical Methods

CuO nanoparticles were synthesized in two different ways monohydrate Cu(CO 2CH13)2·H2O, glacial acetic acid sol-gel method using copper chloride(CuCl electron microscopy (SEM) showed that precipitation and solgel process, respectively, at which the particle size diffraction (XRD)manifested that the pure synthesized powder XRD results showed the particles size of highe infrared spectroscopy (FTIR) were used to describe the prepared CuO nanostru ctures which confirms that the synthesized product is


Introduction
Nanotechnology is a unique branch of science that deals with materials in a very small size between (1-100 nm) with different crystal shapes such as spherical nanoparticles, flower like, Nano rods, Nano ribbons, Nano platelets.The matchless physical and chemical attributes are result from its high surface-to-volume ratio comparing with micro or bulk-sized [1].Authorship of high durability nanomaterials with keeping to chemical pureness, phase selectivity, crystallinity and analogy in particle size with controlled state of agglomeration in a cost procedure is still a challenge to material chemists [2] Various methods have been used to produc CuO.These comprise; rapid precipitation coating, solid state reaction, chemical deposition, sonochemical reaction, sol chemical bath deposition, solvothermal process, electrochemical method, spray pyrolysis, thermal oxidation and hydrothermal route.[3] Khwarizmi Engineering Journal,Vol.12, No. CuO nanoparticles were synthesized in two different ways, firstly by precipitation method using copper acetate •H2O, glacial acetic acid (CH3COOH) and sodium hydroxide(NaOH), gel method using copper chloride(CuCl 2 ), sodium hydroxide (NaOH) and ethanol (C 2 that different CuO nanostructures (spherical and Reef) respectively, at which the particle size was found to be less than 2 µm.X the pure synthesized powder has no inclusions that may exist during preparations.XRD results showed the particles size of highest peak at 38.9°, was equal to (15.93nm).In addition, IR) were used to describe the prepared CuO nanostructures absorption peak at 610 cm firms that the synthesized product is a pure CuO and may be attributed to Cu 2 O infrared active mode.
Nanotechnology is a unique branch of science deals with materials in a very small size different crystal shapes such as spherical nanoparticles, flower like, Nano ribbons, Nano platelets.The matchless physical and chemical attributes are result from its volume ratio comparing with uthorship of highwith keeping to vity, crystallinity ، and analogy in particle size with controlled agglomeration in a cost-effective to material chemists used to produce rapid precipitation, spin coating, solid state reaction, chemical vapor deposition, sonochemical reaction, sol-gel route, chemical bath deposition, solvothermal process, electrochemical method, spray pyrolysis, thermal hydrothermal route.[3] The precipitation and hydrothermal routes are predominating used because they are friendly to the environment , safe and the most attractive and practical route that could be cost-performance and simple implementation is the quick precipitation method Of all the above composition procedures sol gel process has many beneficial.Solitary sol gel installation can yield materials at ultra temperatures, synthesize nearly any substance, co-synthesize two or more substances with each other, exactly observance the microstructure of the end outputs, and punctually dominance the physical ،mechanical, and chemical characterizes of the final Since the chemical and physical attribute of CuO just based on its size an numerous researchers have centered their endeavor on the found of nano construction of CuO in order to stratify them in optoelectronics, biosensors nanomaterials have the merit of a low surface potential partition than that of metals,

University of Technology
firstly by precipitation method using copper acetate (CH3COOH) and sodium hydroxide(NaOH), and secondly by H 6 O).Results of scanning (spherical and Reef) can be formed using to be less than 2 µm.X-ray no inclusions that may exist during preparations.
In addition, Fourier transform absorption peak at 610 cm -1 O infrared active mode.and hydrothermal routes are predominating used because they are friendly to safe and the most attractive and could be used because of its performance and simple implementation is the quick precipitation method [4].
composition procedures solprocess has many beneficial.Solitary solinstallation can yield materials at ultra-low temperatures, synthesize nearly any substance, synthesize two or more substances with each exactly observance the microstructure of outputs, and punctually dominance the mechanical, and chemical outputs [5].Since the chemical and physical attribute of CuO just based on its size and morphology, so numerous researchers have centered their endeavor on the found of nano construction of CuO in order to stratify them in Nano electronics, optoelectronics, biosensors etc [3].CuO have the merit of a low surface than that of metals, which influence on electron field release possession.CuO consider as a potential field emitter, an strong catalytic factor, as well as a valid gas sensing substance.It likewise shows a significant assignment in optoelectronics and solar cell.The metal elements are capable to compose a large variety of oxide compounds.These can take on a great number of constitutional geometries with an electronic structure that able to display metallic,semiconductor or insulator individuality.[6] Oxide nanoparticles can exhibit unique physical and chemical properties due to their limited size and high density of corner or edge surface sites.Particle size is expected to influence three important groups of basic properties in any material.The first one comprises the structural characteristics, namely, the lattice symmetry and cell parameters.Bulk oxides are usually robust and stable systems with well-defined crystallographic structures.However, the growing importance of surface-free energy and stress with decreasing particle size must be considered: changes in thermodynamic stability associated with size can induce modification of cell parameters and/or structural transformations , and in extreme cases the nanoparticle can disappear due to interactions with its surrounding environment and the high surface-free energy .Nanomaterials have become important owing to their small size and large surface area.They exhibit unique properties which are not seen in bulk materials [7] In the present investigation, we have synthesized CuO nanoparticles using low cost solgel process and the most safe and environmentally friendly precipitation method.

First Route: Chemical Precipitation
In order to prepare the nano copper oxide by precipitation route, it was done in two stages: the first was dissolving 1.5g of copper acetate monohydrate(Cu(CO 2 CH 3 ) 2 • H 2 O) in 300 ml of distilled water and then added three drops of glacial acetic acid in a volumetric flask at high mixing speed and 32 0 C. The second stage: dissolving 8 g of sodium hydroxide in 200 ml of distilled water was added drop by drop to the prepared solution in the first stage which turns from bright blue to dark blue, and leaved for one day to turn black.Centrifuge machine is used to filter the black sludge(15min and 490rpm) and washed with water.The sample allowed to dry at room temperature then annealed at temperature 700°C using Carbolite CWF 1200 DegC, 1200 laboratory chamber furnace.The annealed sample of copper oxide nanoparticles was grinded.

Second Route: Sol-Gel method
The synthesis of nano copper oxide by sol-gel method was as fellow: 0.9 g of copper (II) chloride was dissolved in 25 ml of ethanol, 1.5 g of sodium hydroxide was dissolved in 80 ml ethanol.The prepared sodium hydroxide solution was added drop wise to copper chloride solution with constant stirring at room temperature for 30 min .Reaction occurs and colour turns from dark blue to black .Filter paper is used to filter the gel and washed with water.The sample allowed to dry at room temperature then annealed at temperature 700°C using Carbolite CWF 1200 DegC, 1200 laboratory chamber furnace.The annealed sample of copper oxide nanoparticles was grinded.
For the two routes The crystal structure of the CuO nanostructure has been determined by X-ray diffraction (Philips PW 1050 X-ray diffract meter of 1.5 ο A from Cu-Kα, Fourier Transform Infrared Spectroscopy (SHIMADZO IRAFFINITY) and the surface morphology of CuO nanostructure were examined by Scanning Electron Microscope (SEM-VACAN).

Results and Discussion
X-Ray Diffraction Analysis 3.1.
X-ray crystallography considered a tool used for identifying the atomic and molecular structure of a crystal, in which the crystalline atoms cause a beam of incident X-rays to diffract into many specific directions.The crystal structure of CuO nanoparticles prepared by both methods has been showed in Fig .(1) at CuKα (λ = 1.54056A) in the 2θ range from 20° to 80°.The crystallite sizes of the particles were calculated by using Scherrer's equation.D = Kλ / βcosθ ....(1) Where, D is the crystallite size of the particles, K is a shape factor (K=0.9 in this work), λ is the wavelength of the incident1 X-ray (1.54056 A, CuKα), θ is the diffraction angle and β is the fullwidth half maximum.
X-ray diffraction (XRD) pattern higher intensity peaks located at 38.9°, 35.6° and 48.9° which corresponds to the atomic planes (111), ( - 111) and ( -202) respectively.These diffraction planes were well fit with Mohammed et.al [8] who prepare Copper(II)-oxide (Cu=O) nanostructures with different sizes and shapes and their applied in different man daily life applications.In this study the particles size of highest peak (38.9°), is (15.93nm).Table 1, shows size, diffraction angle, Full width at half maximum, d spacing and diffraction Plane of CuO sample.

Infra-red Fourier transformation analysis (FT-IR )
In order to be sure of the chemical and structural nature of the material, FT-IR spectroscopy analysis has been done.CuO nanoparticles prepared in both methods has been scanned from 4000 cm -1 to 400cm -1 as shown in Fig. (2).It can be noticed two active peaks in the range of 400 to 600 cm -1 which corresponding to stretching vibrations of CuO bond in the monoclinic CuO [9].
Absorption bands in the range (1300 and 2000 cm -1 ) are mainly attributed to the chemisorbed and/or physisorbed H 2 O and CO 2 molecules that may attached on the surface of nano-structured CuO crystals [10].Furthermore the absence of absorption peak at 610 cm -1 confirms that the synthesized product is pure CuO and may attributed to Cu 2 O infrared active mode [11] .self-organized into spherical assemblies or ''dandelions'' with a puffy appearance [12] and Kannaki et.al.[13] who used CuSO 4 .5H 2 O shows that how the CuO nanocrystals organized into spherical assemblies.With higher magnification on individual particle it appears like dandelion.Moreover copper (II) chloride that used to prepare CuO structure via sol gel is more like reef with more ability to be agglomerate.

Conclusion
Copper oxide can be synthesized using precipitation and sol-gel methods that were very efficient in producing small sized nanostructures(less than 2 µm).In this study, it has been noticed that the emergence of small nanoscale structures in various forms depending on the type of preparing and this makes it suitable for different applications.It wasobserved that shape, size, and homogeneity of the assynthesized products depend uponvarious reactions conditions, i.e., the nature of the ligand, the relative concentration ofreagents, the solvent, the overall concentration of reagents, the reaction time, the evapo-ration time, and the reaction/evaporation temperature .

. Morphology of Copper Oxide (SEM)
CuO-NPs prepared by both strategies (i.e.precipitation and sol-gel methods) and the size of the produced CuO nanoparticles has been investigated by SEM with different magnifications shown in Fig. (3 and 4) respectively.It can be noticed that there is difference in CuO structure since it tends to be more spherical with quasi architectural by precipitation method with homogeneous distribution and small agglomeration.In the present work copper acetate monohydrate (Cu(CO 2 CH 3 ) 2. H 2 O) has been used to prepare CuO nano particles with spherical shape via prescepitation method, the same morphology has been obtained using Cu (NO 3 ) 2 .3H 2 O as reported by Anandan et al. who reported synthesis CuO crystallites