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3. RESULTS AND DISCUSSION 
3.1. XRD
X-ray diffraction (XRD) at 40Kv was used to estimate the crystalline sizes. The intensity data were collected over a 
2θ range of 20-80
o
. Figure (2) shows the XRD morphology of prepared ZnO nanoparticles at 500 
o
C for 3 hours. In 
our case all the diffraction peaks at angles (2θ
o
) of 31.78°, 33.9°, 36.8°, 47.63°, 56.67°, 62.94° and 67.98°and
correspond to the reflection from (100), (002), (101), (102), (110), (103), (112) crystal planes of the hexagonal 
wurtzite zinc oxide structure (Figure3). all the diffraction peaks agreed with the reported JCPDS data[11], and no 
characteristic peaks were observed other than ZnO. 
 
Khalaf AL ABDULLAH, Sahar AWDE/ Energy Procedia 00 (2017) 000–000 
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Fig.2. XRD pattern of ZnO nanoparticles annealed at 500 
o 
C for 3 hour Fig.3. The wurtzite structure model of ZnO 
The average grain size of ZnO nanoparticles was around 12 nm using the diffraction intensity of ( 101 ) peak from 
Debye -Sherrer equation [12,13]:
…………………….(1) 
where, 0.94 is the shape factor, λ is the X-ray wavelength (1.5148°A),β is the full width at half the maximum 
intensity (FWHM) in radians, and θ is the diffraction Bragg angle. The detailed analysis of the XRD and the 
assignments of various reflections are given in the Table1. 
Table 1.Analysis of XRD and the assignments of various reflections of ZnO
Hkl 
2θ° 
FWHM(deg) 
D(nm) 
100 
31.8° 
0.50 
16.5 
002 
101 
102 
103 
110 
112 
33.9°
36.8°
47.9°
57.9° 
62.8°
68.8° 
0.45 
0.65 
0.4 
0.3 
0.5 
0.6 
18.47 
12.89 
21.75 
29 
17.4 
14.5 
3.2. AFM
The surface morphological studies from AFM was carried out to confirm the actual size of the particles, their growth 
pattern and the distribution of the crystallites. Figure(4) provides a 3D profile of the surface on a nanoscaleof ZnO 
nanoparticles. 
 
Fig.4. AFM images of the prepared ZnO nanoparticle in 3D 

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Khalaf AL ABDULLAH et al. / Energy Procedia 119 (2017) 565–570
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Khalaf AL ABDULLAH, Sahar AWDE/ Energy Procedia 00 (2017) 000–000 
Figure(5) shows the synthesized AFM image of ZnO nanoparticles in 2-dimension. Data are collectedover a selected 
area of the surface of the sample,Areas ranging from approximately (0-7) microns and (0-2) microns in width.Most 
of the particles appear spherical in shape, however some elongated particles and moderately agglomerated particles 
are also present as shown in the AFM images. see Fig(5.a) andFig(5.b). 
Fig.5.AFM images of the prepared ZnO nanoparticle in 2D, (a)7microns area ; (b)2 microns area 
Agglomeration is understood to increase linearly with annealing temperature and hence some degree of 
agglomeration at this temperature (500
o
C) appears unavoidable [7]. But as noticed, most of the agglomerated