Synthesis of Pure Nano semiconductor Oxide ZnO with Different AgNO3 Concentrations

Zinc oxide nanoparticles sample is prepared by the precipitation method. This method involves using zinc nitrate and urea in aqueous solution, then (AgNO3) Solution with different concentrations is added. The obtained precipitated compound is structurally characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). The average particle size of nanoparticles is around 28nm in pure, the average particle size reaches 26nm with adding AgNO3 (0.05g in100ml =0.002 M) (0.1g in100ml=0.0058M), AgNO3 (0.2g in 100ml=0.01M) was 25nm. The FTIR result shows the existence of -CO, -CO2, -OH, and -NO2 groups in sample and oxides (ZnO, Ag2O).and used an atomic force microscope and microscope scanning electron to model the record.


Introduction:
Zinc oxide is one of the semiconductor inorganic compounds with the formula ZnO. It usually appears as a white powder nearly insoluble in water, which is widely used as an additive into numerous materials and products including, paints, glass, cement, ceramics, rubber lubricants, plastics, ointments, adhesives, pigments, sealants, and foods batteries. ZnO exists in the earth crust; however, much of the ZnO used commercially is produced synthetically. Due to a wide band gap of ZnO oxide with an energy gap of 3.37eV at room temperature which has been used considerably in photochemical properties [1][2][3][4]. ZnO nanostructures have a great advantage in the process of catalytic reaction due to their large surface area and high catalytic activity ]5 [ Nanoscience is the study of phenomena on a nanometer scale. Atoms are a few tenths of a nanometer in diameter and molecules are typically a few nanometers in size. Nanometer is a magical point on the length scale for this is the point where the smallest man-made devices meet the atoms and molecules of the natural world. Typically, nano means 10 -9 , so a nanometer is one billionth of a meter and is the unit of length that is generally most appropriate for describing the size of single molecule. Nanometer objects are too small to be seen with check eye. If one wants to see a 10 nm sized marble in his hand, his eye would have to be smaller than a human hair. Anyhow, the Open Access rough definition of Nanoscience could be anything which has at least one dimension less than 100 nanometer [6].

Fourier Transforms Infrared
Spectrophotometer (FTIR) model himadzu (Japan) has been used to determine the IR-spectra of ZnO in the range (400-4000)cm -1 .

Atomic Force
Microscope AA 3000, scanning probe microscope, Angstrom advanced Inc., (USA), has been used to study the topography of the prepared Nanoparticles ZnO.

X-Ray Diffraction analysis achieved in the Ministry of Science and Technology
-materials research department by using SHIMADZU (XRD -7000) diffractometer /Japan , measure the particle size and morphology of the synthesized nanoparticles.

Methods:
Urea (CO (NH 2 ) 2 )99%, BDH, Zinc nitrate (Zn (NO 3 ) 2 .6H 2 O) 99%, BDH, Silver nitrate (AgNO 3 )99%, BDH, and Double distilled water are used as starting material for the preparation of samples. At the outset, 4.7g of Zinc nitrate is dissolved in 50 ml of distilled water stirring for 30 minutes. At the same time 3.0g of urea is dissolved in another 50ml of distilled water, also under stirring for 30 minutes. Then the urea solution is added drop by drop to zinc nitrate solution with strong stirring at 70 ° C for 2 hours to allow full growth of nanoparticles. When adding the urea solution to the zinc is complete, different concentrations of silver nitrate as a dopping material are added .The white precursor product is centrifuged at 8000 rpm for 10 min and washed with distilled water to remove any impurities or possible absorbed ions. The obtained product is calcined at 500 °C in air atmosphere for 3 hr. using burning furnace. ]7[

Scanning Electron Microscopic (SEM)
Electron photomicrographs of ZnO nanoparticles obtained from direct precipitation of 4.7 g Zn(NO 3 ) 2 .6H 2 O and 3.0 g CO(NH 2 ) 2 calcined at 500 °C for 3 hr. as shown in Figure.3(a,b,c,d), reveal the SEM images of ZnO nanoparticles and ZnO after adding dope AgNO 3 with (0.05,0.1.0.2),It is observed that the particles are well defined and small spherical shaped with agglomerated particles as shown in Figure.

Fourier Transforms Infrared Spectroscopy
Absorbance spectra in infrared region for the pure ZnO particles powder before and after adding dope AgNO 3 as shown Figures. 4a, 4b, 4c, and (4d

Atomic force microscopy (AFM)
Atomic Force Microscopic AFM is a powerful characterization tool for surfaces at the micro and nano level as a result of the superior resolution capabilities of the instrument. The AFM image, Figure 5(a,b,c,d), of ZnO and the different doping Ag malaria reseal clear differences in particle size surface roughness and 10 point high as shown in Table ( 2) respectively which reflex weed control on particle formation at the nano scale as shown in Table(2) ]11-12[ .

Conclusions:
In this work, the pure ZnO nanoparticles with adding different concentrations of AgNO 3 (0.002 M, 0.0058 M, 0.01 M) are successfully prepared by the direct precipitation method using zinc nitrate as zinc source and urea as precipitating agent in aqueous solution, sliver nitrate is added in different concentration. In XRD analysis, the size range of the generated ZnO powder is approximately 25-28 nm and the nanoparticle size decreases when different concentrations of silver nitrate are added .The SEM analysis shows that the particles morphology is of a spherical structure.
The FT-IR spectrum shows the existence of OH-, -CO2, -NO -2 and -CO groups in unclaimed sample .The band gap is lower for synthesized ZnO nanoparticles than their bulk counterparts. Thus, the synthesis of ZnO nanoparticles by direct precipitation method is simple.