THE EFFECT OF CALCINATION TEMPERATURES ON THE
PROPERTIES OF ZNO NANOPARTICLES SYNTHESIZED BY USING LEAVES EXTRACTS OF PINUS
BRUTIA TREE
Sherwan
M. Mahdi Ismail 1*, Sabah M. Ahmed 1
1 Department
of Physics, College of Science, University of Duhok, Kurdistan Region, Iraq
Received: 15
Dec., 2022 / Accepted: 8 Jan., 2023 / Published: 7 June, 2023 https://doi.org/10.25271/sjuoz.2023.11.2.1087
ABSTRACT:
Pinus Brutia (PB)
tree leaf extracts were used to produce zinc oxide (ZnO)
nanoparticles. The study of the
PB tree extracts at
several calcination temperatures from (200 to 500) oC on the
formation of ZnO NPs'
characteristics has been
investigated using various characterization techniques. The
chosen plant PB had its findings
at both examinations of
FTIR and UV-Visible spectroscopies shown and offered to be a superior option
for the GS ZnO NPs at various pH levels. PB tree
leaf extracts' UV-visible spectra revealed one distinguishable absorption peak
at 275.3 nm. The study of the FESEM
results showed that the Green Synthesized (GS) ZnO
NPs' orientation, shape, and dimensions are significantly impacted by the
calcination temperatures. The ZnO NPs are also shown
by the XRD data to have hexagonal wurtzite crystal structures that have
particle sizes at (002)
peak falling within the range between (10 to 24) nm.
The UV-Visible study of the ZnO NPs
showed a strong peak absorbance for ZnO NPs that were calcined at various temperatures, with
high UV absorption below 400 nm. The obtained
energy band gap (Eg) is
located in the region between (2.65 and 2.747)
eV, narrowing as the
calcination temperature rises. The ZnO NPs that were
calcined at a temperature of 500 oC also
had superior quality and outperformed those produced at other calcination
temperatures, according to all of the analyzed results and properties of the ZnO NPs.
Keywords: Calcination Temperature, ZnO NPs, Pinus Brutia, Green Method, Tree Extract
1.
INTRODUCTION
One of the most rapidly
developing and ever-evolving fields is nanotechnology,
regarded as the industrial revolution of this time.
With the potential to form
and underpin an advancement in a wide
range of biotechnology and technology (Azeez
et. al., 2020).
Many research and
commercial
fields, including electronics,
information technology, biology, agriculture, chemistry, and physics,
have used nanotechnology (Abdelbaky
et. al., 2022). Due
to the advanced chemical and
biological properties of nanoparticles, they have
many applications in
science.
These advanced properties
of nanoparticles can’t be found in the bulk material of the same chemicals
(Khan et. al., 2019).
The
unique property of nanoparticles (NPs) is that they have a high
surface-to-volume ratio. This makes them good
candidates for performance-oriented
applications like
cosmetics, creating
gas sensors, energy
storage, electronics
devices, food
packaging, and environmental remediation,
which promotes their
incorporation into a wide range of technology
(Nilavukkarasi et.
al., 2020;
Zheng, et. al., 2020). It
is believed that metal oxide nanoparticles are more advantageous
than other nanoparticles due to their unique physical, chemical, and biological
properties (Waseem
et. al., 2020). ZnO
nanoparticles, known for their remarkable piezoelectric, optoelectronics,
pyroelectric, semiconducting, catalysis, and antimicrobial properties, are
among them. They have been recognized as a material with great potential in all
fields,
such as physics, biology, engineering, chemistry, and so on
(Bettini et. al., 2015;
Hong et. al., 2011).
Numerous
negative side effects and toxicities are brought on by the reduction and
capping of nanoparticles with toxic chemicals.
Consequently, the use of plant extracts in the
synthesis of metal oxide nanoparticles has grown in significance
(Meron et. al., 2020). Compared
to conventional chemicals, this method is more environmentally friendly and has
a quicker reaction time. Plant extracts have a variety of bioactive molecules
that help stabilize and reduce nanoparticles
(Seyyed et. al., 2020). According
to past research,
researchers managed to form Zinc Oxide NPs through plant extracts;
a large number
of plants that are used to synthesize
ZnO NPs can be found in literature, for
example,
Trifolium pratense, Aloe vera, Vitex trifolia, Matricaria chamomilla, Camellia sinensis, Azadirachta indica, Artocarpus gomezianus,
Olea europaea, and Duranta erecta
(Meron et. al., 2020).
This
research focuses on the production of ZnO
nanoparticles through
the green method
from Pinus
Brutia (PB)
tree leaf extracts. The effect of different
calcination temperatures in
the range of (200
to 500) oC
on the quality characteristics of GS ZnO NPs
has been studied. The
importance of this research
is highlighted by a thorough examination
of the various factors that influence the shape, size, particle size
distribution, optical properties, crystal
structure, and energy band
gap of ZnO
NPs. The role of green plant biomolecules in the bioreduction
of metal salts during nanoparticle extraction has been demonstrated.
2.
EXPERIMENTAL
METHOD
The
zinc salt (Zinc nitrate hexahydrate) [Zn (NO3)2. 6H2O] with
molecular weight (297.48
g/mol) and
purity greater than (99%) as
well as sodium hydroxide powder [(NaOH) molecular weight (40
g/mol)] were purchased
from Sigma-Aldrich and used for this study with no further treatment.
The
60 grams of fresh green PB tree leaves were
collected, washed thoroughly with distilled water to remove any dust or
pollution, cut into small pieces, and then placed in 600 ml of distilled water.
The mixture was heated at 75 oC
for 50 minutes, after which the PB leaf extracts were filtered many times using
filter paper with pore sizes of 8 μm and
centrifuged extensively (Karam et al., 2022).
The characterization using a
UV-V spectrometer and FTIR were
checked, and the extracts were stored in a cold place for future use.
To
prepare the GS ZnO NPs at different calcination
temperatures, 60 ml of PB tree extracts from the leaf were added dropwise to (0.1
M) in 60 ml of zinc nitrate
hexahydrate [Zn (NO3)2. 6H2O] dropwise under magnetic stirring at 75 oC
degrees for 30 minutes. Later, the pH of the prepared GS mixture was adjusted
to 8 by adding drops of (NaOH) sodium hydroxide while the magnetic stirrer was
turned on. A pH meter was used to monitor the pH of the
solution continuously. The color and
transparency of the mixture began to change as the pH was adjusted,
indicating that a reaction between the metal salt and the plant extracts
occurred,
and ZnO NPs were formed.
For 8 hours, the setup was kept on magnetic
stirring at 75 oC
until all of the water evaporated (Amad et. al. 2022).
After 8 hours on the heater stirrer, the leftovers from the mixture were
calcined and purified in the annealing furnace for 2 hours at several
calcination’
temperatures. The final product of GS
ZnO NPs was then stored in a tube for
characterization, as shown in Figure 1. For different calcination temperatures
of the GS mixture, such as (200, 300, 400, and 500) oC
and the fabricated samples
were labeled (a), (b), (c), and (d), respectively.
Figure 1. Schematic
Diagram representation of the ZnO NPs using Green Synthesized
at different Calcinations Temperatures using Leaf extracts of the PB
tree.
PB tree leaf extracts and
the resulting Zinc Oxide nanoparticles are
examined using a UV-Visible
double beam spectrophotometer by
Agilent Technologies carrier series to determine their optical characteristics
(Cary 100 UV-Vis). The wavelengths of
absorption of ZnO NPs and leaf extracts were measured
between 200 and 800 nm. A surface study including shape, chemical composition,
size, and orientation of ZnO NPs, studying the size
and crystal formation, stress and strain,
and quality of the produced Zinc Oxide nanoparticles
at different calcination temperatures were
all carried out using PB leaf extracts and the various functional groups that
appeared in them (Nicolet IS10, Thermo Scientific,
Waltham, MA, USA).
The
testing range for Fourier Transform Infrared Spectroscopy (FTIR) was set to
begin at 400 to 4000 cm-1, followed by using
the Supra 55VP from Carl Zeiss AG.
We performed (EDX)
energy-dispersive X-ray spectroscopy and
(FE-SEM) field
emission scanning electron microscopy with CuK
radiation at 1.54050 angstroms and scanning angles between 20 and 80 degrees.
3.
RESULTS
AND DISCUSSION
The Fourier Transform
functional groups (FTIR) associated with reductive biomolecules have been
investigated using infrared of the tree extract spectra and the functional
groups that support the reduction of ZnO (Aswathy et. a., 2021; Barzinjy
et. al., 2020). Figure 2 depicts the FTIR spectrum of the PB tree leaf
extracts. As can be seen, this spectrum exhibits many peaks between (400- 4000)
cm-1. In essence, the FTIR
spectrum may be separated into two regions: first, from (0-1500) cm-1 is the region that can
be called the fingerprint; in this region, it is possible to see that plant
extract that is utilized to create ZnO nanoparticles.
Second, the functional group region spans the range of (1800- 4000) cm-1. FTIR spectra typically
provide information about the composition of internal components that connect
all stages of matter (Norouzi et. al., 2019;
Srivastava, et. al. 2013 and Zandi et. al., 2011). Peak
absorption at 815 cm-1 is
mostly caused by C-H bond 1,4-disubstitution (para). The phosphate ion of common
inorganic ions is the peak that was observed at 1072 cm-1. The
measured absorption peak for the aryl-O stretch of ether and oxy molecule,
which includes aromatic ethers, is at 1253 cm-1. At
1340 cm-1, CN
stretch, the aromatic primary amine is at its highest absorption. Additionally,
the peak of primary amine, or 1608 cm-1 NH
bend, is seen. The 2931 cm-1 peak
under investigation is a Methylene C-H asym./sym.
stretch (>CH2). The aliphatic secondary amine and >N-H stretch of
secondary amino, respectively, peak at 3334 cm-1 and
3363 cm-1.
Additionally, aliphatic primary amine and NH stretch peaks at 3385 cm-1. Meanwhile,
the obtained peak at 3421 cm-1 is an
NH stretch and an aromatic primary amine (Kim et. al., 2001).
Figure 2. FTIR Spectrum
Analysis of the PB Tree Leaf Extracts
The
leaf extracts' UV-visible spectrum of the PB tree is shown in Figure 3.
One maximum peak was visible at a wavelength of
(275.3) nm. This peak can be
explained by the phytochemicals found in the leaf extracts of the PB tree,
which is plausible given that OH groups serve as numerous stabilizing agents.
NPs can be created by bio-reducing
(Singh et. al., 2016).
Since these phytochemicals are antioxidants and free of hazardous substances,
they continue to be very effective at reducing metal ions and their stability at
the nanoscale. Phytochemicals can
produce nanoparticles of varied shapes and sizes simultaneously (Hocine et. al., 2016). Electromagnetic
waves carry out the creation of NPs, and the spectra of the
(UV-Vis.) indicated the absorption peak (SPR)
surface plasmon resonance and retains electron
(e) oscillations in the conduction-band reactive metal ion reduction (Pai
2019).
Figure 3. UV-Vis. Spectrum Analysis of the
Pinus Brutia Tree Leaf Extracts
The
size, density, distribution, shape, formation,
and orientation at different
calcination temperatures for ZnO nanoparticles
have been studied by using the FESEM analysis,
as shown in Figure 4. It can be observed
that the ZnO nanoparticles were formed by using Pinus
Brutia tree leaf extraction and modified by increasing
several calcination temperatures from 200 oC
to 500 oC.
Also, it is
noticeable from Figures
4 (a) to 4 (c) that the
ZnO NPs were successfully produced with high density and
had a
high rate of agglomeration
due to the electrostatic charge. Due
to a high agglomeration rate, the average size distribution was not estimated
for the ZnO NPS samples synthesized with calcination
temperatures 200, 300, an. The agglomeration makes
the NPs stick together,
making it challenging to observe the NPs.
Whereas, the
shape and size of Zinc
oxide nanoparticles
increase
with increasing the
calcination temperature. The novelty of this study is
giving a good idea about
understanding the calcination
temperature of the final product of ZnO NPs.
In Figure
4, as the calcination temperature increases, one can clearly understand that
the calcination temperature plays an essential role in the deagglomeration of
the ZnO NPs.
(c) (d) (a) (b)
Figure
4. The effect of Various Calcination Temperatures
on the Morphological Properties of Zinc Oxide Nanoparticles Produced by utilizing the leaf Extracts of the Tree of Pinus Brutia: (a) 200 oC, (b) 300 oC, (c) 400 oC, and (d) 500 oC.
The green synthesis
nanoparticles, distinguished by significant aggregation formation, are where ZnO NPs are
typically found. This is
a result of the larger surface area and lasting affinities of biosynthetic NPs that
cause them to clump or aggregate together (Vidya
et. al. 2013). One
might assert that ecological factors significantly affect stability and NP
agglomeration. As a result, as the
nanoparticles grew, they came
together, and a symmetrical
cluster appeared on its own (Shim
et. al., 2019). While the
calcination temperature the size,
shape, and
other characteristics have been
studied. When the
temperature is increased to 500
oC, the ZnO NPs
have been in spherical
shapes, and the majority of these NPs were gathered together to form
clusters with high distribution
densities as shown in figure
4, which shows
that the ZnO NPs have narrow size
distribution, shape, and low rate of
agglomerations. They have an average size of about 65.70
nm.
The
elementally chemical composition
of the biosynthesized ZnO
NPs is investigated and
evaluated using EDX spectroscopic analysis in
different calcination temperatures
in the range
of (200-500) oC.
One
can notice that the EDX analysis.
It is apparent that both
the Oxygen (O) and Zinc (Zn) elements are present, eliminating the possibility
of any impurity’s indicators
with respect to the orientation of the features structures of the green
synthesis ZnO NPs. The
Au energy was
observed because
the ZnO NPs were coated with gold NPs before taking
the EDX and FESEM analysis.
ZnO
nanoparticles
exhibit unique features, as evidenced by the two highly directed Zn peaks in
the EDX spectrums that were about 1.1 and 8.7 keV and an oxygen signal at 0.5
keV (Amad
et. al., 2022). All green synthesis ZnO NPs made at
different pH levels have approximately the same zinc (Zn) to oxygen (O) atomic
ratio. Quantitative characterizations from (EDX) show that the studied
nanoparticles are pure GS ZnO because the computed
(MR) molecular ratio of Zinc. Oxygen in the generated nanoparticles is 1:1. The weight percentage of
GS ZnO nanoparticles composition has been obtained
using EDX analysis at numerous calcination temperatures which are Zn (70.2%, 70.8%, 82.6%, and 82.4%)
and O (29.8%, 29.2%, 17.4%, and 17.6%) for calcination temperatures 200 oC, 300 oC, 400 oC, and 500 oC, respectively.
(a) (b) (c) (d)
Figure 5. The effect of the Various Calcination Temperatures
on the Elemental Chemical Compositions (EDS)of Zinc Oxide Nanoparticles Produced by utilizing the leaf Extracts of the of Pinus Brutia Tree: (a) 200 oC, (b) 300 oC, (c) 400 oC, and (d) 500 oC.
The
structural properties of the fabricated ZnO NPs from
Pinus Brutia plant leaf extracts with
various calcination temperatures were investigated using the non-distractive
XRD technique, as shown in Figure 6.
The investigated diffractions for all XRD patterns of ZnO
NPs were biosynthesized with hexagonal (wurtzite) polycrystalline crystal
structures and indexed with the
standard
XRD database (JCPDS card number 98-009-4004).
Further evidence that the
ZnO NPs made from Pinus Brutia
tree leaf extracts at various calcination temperatures were formed with
extremely high purity of ZnO nanocrystal phases came
from the lack of peak diffraction from other defects (impurities). Figure 6
shows that (100), (002), and (101), which are the three main and firm
diffraction peaks with changing intensities that are present in the X-ray
diffraction peaks for all calcination temperatures, changed in intensity as the
ZnO NPs were calcinated at various temperatures. The
diffraction peaks along the (101) plane are also more
apparent and robust; also, the XRD results and behaviors displayed are completely
consistent with other studies (Barzinjy et. al., 2020, Dey et.
al., 2022, Abdo et. al. 2021, Abel et. al. 2021).
Figure
6. The effect of the Various Calcination Temperatures
on the XRD Patterns of Zinc
Oxide Nanoparticles
Produced by utilizing the leaf
Extracts of the Tree of Pinus Brutia
The
average particle size of ZnO NPs produced at various
calcination temperatures of the three dominant planes, (100), (002), and (101),
is determined using the Debye-Scherrer equation (Abdulrahman
et. al., 2020). Table 1 displays the
results of (D).
where K, D, the angle
of diffraction, the wavelength
of the X-ray beam, and the
shape factor of the crystallite are, in
turn, the (FWHM) Full Width at
Half Maximum
of the peak, respectively.
When ZnO NPs are calcinated from 200 oC to 500
oC, the
average particle size has been changed. The annealing process causes the
particles to reorient due to heat energy, which also helps to reduce crystal
structural flaws. At the same time, it results in variations in the average size of
the particles of ZnO NPs (Korake et. al. 2014).
The
dislocation density (
Where D is the crystallite
size
From
Table 1, one can conclude that the calcination temperature significantly
affects the number of defects
present in the Zinc Oxide
NPs. The following equations (Abdulrahman et. al.,
2020) have been implemented
to evaluate the effect
of various calcination
temperatures
on the length of the bond as well for hexagonal-cell volume of produced ZnO nanoparticles along the planes
of (100), (002), and (101).
The results are reported in Table 1.
The
length of the "c" axis is a parameter related to the ratio of
"c/a," and "u" represents the distance that the atoms
traveled in the direction of the subsequent atoms, according to the formula
below (Abdulrahman
et. al., 2020);
To
investigate (V) the hexagonal cell's volume, the below formula has been
employed (Abdulrahman et. al.,
2020):
Table 1: The effects of the
calcination temperatures on the ZnO nanoparticle's volume,
bond length, dislocation density, crystal size, and (100), (002), and (003)
peak diffraction planes (101)
Calcination
Temperature
(oC) |
D (nm) |
δ ×10-5 (Å-2) |
V(Å3) |
L
(Å) |
|
200 |
100 |
23.989 |
1.737 |
50.946 |
2.025 |
300 |
100 |
41.951 |
0.568 |
52.318 |
2.044 |
400 |
100 |
20.989 |
2.269 |
51.033 |
2.027 |
500 |
100 |
23.991 |
1.737 |
50.814 |
2.024 |
200 |
002 |
21.131 |
2.239 |
40.674 |
1.879 |
300 |
002 |
10.563 |
8.961 |
40.903 |
1.883 |
400 |
002 |
16.914 |
3.495 |
40.003 |
1.869 |
500 |
002 |
24.154 |
1.714 |
40.468 |
1.875 |
200 |
101 |
42.488 |
0.554 |
34.759 |
1.783 |
300 |
101 |
33.974 |
0.866 |
35.218 |
1.791 |
400 |
101 |
21.248 |
2.215 |
34.546 |
1.779 |
500 |
101 |
24.286 |
1.700 |
34.489 |
1.778 |
By
applying Bragg's
law (Ahmed et. al., 2020),
(a & c) the lattice constants, with the three main planes (100), (002), and
(101) of hexagonal Zinc Oxide
NPs structure with various calcination temperatures have been calculated. The
results of (a & c) are shown in Table 2.
The
diffraction
peak's angle is denoted by the symbol " ɵ"
and " λ " also denotes the X-ray source’s wavelength.
Because of the following
equations (Ahmed et. al., 2020),
the strains (Ƹc) and (Ƹa), the
main planes of the a-axis and c-axis, respectively, of the Zinc
Oxide Nanoparticles produced at different
calcination temperatures, are considered. The
results of (Ƹc) and (Ƹa) are
listed in Table 2.
ao
and co
are
indicated as the standard lattice constants targeted in the database.
There
are unbound Zinc
Oxide Nanoparticles
everywhere.
A
compressive strain has been defined as a negative strain value, which includes
lattice growth. While the expansion in the lattice is shown by the positive
sign of the strain value, it
is connected to the tensile strain (Ahmed et. al., 2020;
Ahmed et. al., 2021).
The inter-planer distance of biosynthesized ZnO NPs is significantly impacted by increasing the
calcination temperature, as shown in Table 2,
which provides further evidence. To study this, the
following equation (Ahmed et. al., 2021)
has been used:
Anywhere h, k, and l are
situated Miller indices as per X-Ray diffraction peaks.
Table 2: Impact of
Several Calcination Temperatures on the Lattice Parameters and Zinc
Oxide (wurtzite-hexagonal)
Structure properties of the produced Zinc
Oxide Nanoparticles with the Sharper Peaks
Diffraction planes of (100), (002), and (101)
Calcination
Temperature (oC) |
Plane |
FWHM |
2θ |
c
(Å) |
Ƹc% |
a
(Å) |
Ƹa% |
d
(Å) |
200 |
100 |
0.3444 |
31.883 |
5.609 |
7.807 |
3.238 |
-0.262 |
2.805 |
300 |
100 |
0.1968 |
31.5944 |
5.659 |
8.766 |
3.267 |
0.625 |
2.829 |
400 |
100 |
0.3936 |
31.8645 |
5.612 |
7.868 |
3.240 |
-0.206 |
2.806 |
500 |
100 |
0.3444 |
31.9114 |
5.604 |
7.714 |
3.236 |
-0.349 |
2.802 |
200 |
002 |
0.3936 |
34.4427 |
5.203 |
0.011 |
3.004 |
-7.474 |
2.602 |
300 |
002 |
0.7872 |
34.3765 |
5.213 |
0.198 |
3.009 |
-7.302 |
2.606 |
400 |
002 |
0.492 |
34.6403 |
5.175 |
-0.542 |
2.987 |
-7.986 |
2.587 |
500 |
002 |
0.3444 |
34.5031 |
5.195 |
-0.158 |
2.999 |
-7.631 |
2.597 |
200 |
101 |
0.1968 |
36.3581 |
4.938 |
-5.092 |
2.851 |
-12.197 |
2.469 |
300 |
101 |
0.246 |
36.194 |
4.959 |
-4.677 |
2.863 |
-11.812 |
2.479 |
400 |
101 |
0.3936 |
36.4351 |
4.928 |
-5.286 |
2.845 |
-12.376 |
2.463 |
500 |
101 |
0.3444 |
36.4558 |
4.925 |
-5.339 |
2.844 |
-12.424 |
2.463 |
The optical
characteristics of GS ZnO NPs which
were calcinated with
different temperatures from 200 oC to 500
oC were
studied using the double beam UV-Visible spectrophotometer
by observing the absorption
spectrum. The absorption spectrums of GS ZnO NPs
produced using extracts of the leaf of PB tree at different calcination
temperatures in the wavelength range between (300 to 800) nm is shown in Figure
7. The GS ZnO NPs powder exhibits strong (UV) absorption, a high rate
of absorbance less than 400 nm, remarkable clarity, and a narrow visible
absorption range when the calcination temperature is varied (Roza et. al., 2015).
Figure
7. The effect of the Various Calcination Temperatures
on the Optical Absorption Properties of Zinc Oxide Nanoparticles Produced by utilizing
the leaf Extracts of the Tree of Pinus Brutia
Low
absorption values at long wavelengths are caused by defects in GS ZnO NP that rely on the crystal's quality, lattice parameters,
crystal size, and oxygen vacancies that exist as donor impurities (Shabannia et. al., 2014).
In the wavelength range of (381-388.5) nm,
exciton absorption and a strong UV absorption edge have been observed. These
phenomena are connected to the (Eg) optical Energy
Band-gap of the GS ZnO nanoparticles at varied
calcination temperatures. When the peak is
sharpened, monodispersed ZnO NPs are produced as a
result of the (SPR). Rather than following the rule of thumb, the maximum peak
absorption of Zinc Oxide Nanoparticles
was discovered to be in the range
between 350 and 400 nm. The value obtained is
smaller than the one that bulk Zinc Oxide
anticipated using 381
nm to 388.5
nm wavelengths, and it also exhibited a blue shift in excitonic absorption,
suggesting a slight quantum confinement effect
(Barzinjy et. al.,
2020).
Figure
8 illustrates the projection of the linear component of (ɑhv)2 versus
(h) using transmittance spectra. The Tauc formula is
then used to determine the optical band-gap energy of GS ZnO
NPs using PB tree leaf extracts at various calcination temperatures (Abdulrahman
et. al., 2022):
Where
The (
“T “and “d” are the
transmittances and thickness aimed at ZnO samples,
Figure
8. The Influence of the Different Calcination Temperatures on the Optical
Energy Band Gap of Zinc
Oxide Nanoparticles
Produced by utilizing the leaf Extracts of the Tree of Pinus Brutia. Tauc-plot Versus Eg.
Figure 9. FTIR Spectrum
Analysis of the Zinc
Oxide Nanoparticles
synthesized using the extracts
of the leaf of
the Pinus Brutia Tree when Calcinated with several
Temperatures
From Figure 8, one can
see that the transition region of the produced GS ZnO
NPs with various calcination temperatures is roughly in the range of (2.65-2.7)
eV, which is represented by the Eg corresponding to
the transition band between both valance and conduction bands, that denotes the
Eg of the semiconductor ZnO
NPs (Roza et. al., 2015). Also,
from the plots in Figure 8, the obtained Eg of
synthesized GS ZnO NPs with different calcination
temperatures are (2.747, 2.711, 2.675, and 2.625) eV, and (200, 300, 400, and
500) oC,
respectively. The Eg is decreased with increasing the
calcination temperature from 200 oC to 500
oC. This
decrease in the Eg of the nanoparticles is due to the
change in the lattice
constant of the tree’s leaf extracts; because of the use of plant extracts, a
lowering in the band gap is
expected (Khan et. al., 2019). This
discovery, which was made primarily in GS NPs, is not contradictory with
quantum (effect) confinement occurrences. GS NPs are typically more active than
NPs produced by other fabrication methods.
FTIR spectrum analysis
has been employed to examine and study the functional group, purity, and
composition of the obtained ZnO nanoparticles
produced via the GS technique, and by displaying in Figure 9. Figure 9
demonstrates that no peaks were apparent in the observation range and showed the purity of the
GS ZnO nanoparticles which were calcinated with
different temperatures. The FTIR spectrum of ZnO NPs calcinated with the
temperature of 200 oC
shows different absorption peaks. The peaks 538 cm-1 and
817 cm-1
are related to the
Aliphatic Iodo compounds, C-I stretch, peroxides,
and C-O-O- stretch, respectively. Also, the obtained peaks (1049, 1310,
1387,1541, 1643, 1804, and
1935) cm-1 are
related to compounds of
Primary amine, CN stretch, Aromatic tertiary amine, CN stretch, Common
inorganic ions, Nitrate ion, Carboxylate (carboxylic
acid salt), Quinone or conjugated ketone of
Carbonyl compound, cm-1
Carbonyl compound of Acid (acyl) halide, and Aromatic ring (aryl) of Aromatic
combination bands, respectively. The investigated peak (2220, 2850, 2921, 3409,
3605, 3695, and 3872) cm-1 are
related to the compound of C≡C Medial alkyne (disubstituted), Methoxy,
C-H stretch (CH3-O-), Methylene C-H asym./sym,
Stretch, Normal ‘‘polymeric’’ OH stretch, Nonbonded hydroxy group, OH
stretch, Primary alcohol, OH stretch, and
O-H stretching of alcohol, respectively.
The
FTIR spectrum of ZnO NPs shows several
absorption peaks, which include (632, 781, 1049, 1425,
1541, 1643, and1864) cm-1 that are related to
Acetylenic(alkyne) of Alkyne C-H bend, Aromatic ring (aryl) of C-H
1,3-Disubstitution (meta),
Primary amine, CN stretch, Methylene (>CH2) of Methylene C-H bend,
Carboxylate (carboxylic acid salt), Quinone or conjugated ketone of Carbonyl
compound, and Carbonyl compound of Acid (acyl) halide, respectively. While the
obtained peaks (2196, 2481, 3415, 3687, 3742, and
3871) cm-1 were
related to the compounds C≡C Medial alkyne (disubstituted), strong O=C=O
stretching carbon dioxide, Normal ‘‘polymeric’’ OH stretch, Nonbonded hydroxy
group, OH stretch, Primary alcohol, OH stretch, and
O-H stretching of alcohol, respectively.
Different
absorption peaks were seen in the ZnO Nanoparticles'
FTIR spectrum that was
calcinated with the temperature
of 400 oC
as shown in Figure 9. The observed peaks were (669, 716, 1102, 1425, 1541, and
1643) cm-1 that were
related to the compounds of Acetylenic(alkyne) of Alkyne C-H bend, Aromatic
ring (aryl) of C-H 1,3-Disubstitution (meta), Secondary alcohol, C-O stretch, Common
inorganic ions of Carbonate ion, Nitrogen-oxy compounds of Aliphatic nitro
compounds, and Quinone or conjugated ketone of Carbonyl compound, respectively.
While peaks (2273, 2356, 2494, 2886, 3469, 3611, 3736, 3801, and
3872) cm-1 are
concerned with
C≡C Medial alkyne (disubstituted),
stretching O=C=O carbon
dioxide, strong O=C=O stretching carbon dioxide, Methoxy, C-H stretch (CH3-O-),
Normal ‘‘polymeric’’ OH stretch, Nonbonded hydroxy group, OH stretch, Primary
alcohol, OH stretch, and O-H stretching of alcohol, respectively.
In addition, when ZnO NPs are calcinated at
500 oC,
several absorption peaks are
investigated,
as shown in Figure 9. The absorption peaks observed at (574,
627, 835, 878, and 991)
cm-1 are related to the
Disulfides (C-S stretch), and Alkyne C-H bend, Peroxides, C-O-O- stretch band,
and Aromatic C-H in-plane bend, respectively. Additionally,
the seven peaks absorption were seen in the (1000-2000) cm-1,
which are (1134,
1343, 1425, 1521, 1652, 1747, and 1813)
cm-1 that
are owing to the bands of
the Aliphatic fluoro compounds, C-F stretch primary
or secondary, OH in-plane band,
Carbonate ion of Common inorganic ions, Carboxylate (carboxylic acid salt),
Amide of Carbonyl compound, Ester of Carbonyl compound, and Acid (acyl) halide,
respectively. Additionally, the
examined absorption peak lies in the region between 2000 cm-1
to 4000 cm-1,
including (2189,
2870, 2976, 3566, 3739, and
3876)
cm-1, which
are related to the bands of Cyanide ion, thiocyanate ion, related ions, Methyl
C-H asym./sym, Stretch, internally bonded OH stretch, and
O-H stretching of alcohol, respectively.
4.
CONCLUSION
The
ZnO NPs have been successfully produced at a low cost
using the extracts from the leaf of the Pinus Brutia
tree. The influence of the tree extracts from PB and ZnO
NPs' properties, including their crystal structure, size, orientation, average
size, shape, density distribution, functional group, elemental composition, and
optical characteristics, have been studied at various calcination temperatures.
According to the
PB tree leaf extracts analysis, the PB tree is a better option for the biosynthesis
of GS Zinc Oxide Nanoparticles at different calcination temperatures.
Also, the results displayed that the change in the calcination
(annealing) temperature significantly affects
all of the obtained properties of the ZnO NPs. The
calcination temperature change greatly
impacts the quality and average crystal size of the generated
hexagonal-wurtzite Zinc Oxide Nanoparticles.
The FESEM analysis showed that the Zinc Oxide Nanoparticles are
significantly
affected in
their orientation, shape, and size by the
calcination temperatures. The
GS ZnO nanoparticles' UV-Visible analysis revealed a
significant peak for all Zinc Oxide
NPs made at various temperatures of calcination,
a considerable
absorbance in the UV region and below 400 nm, and a poor absorption rate in the
visible region. The (Eg), which denotes the
Energy Band Gap,
lays between the (2.65-2.747)
eV region,
and it decreases as the calcination temperature increases.
Additionally,
the FTIR spectra of formed ZnO NPs
with various calcination
temperatures
showed no apparent peak in the visible range, demonstrating pure Zinc
Oxide Nanoparticles produced by employing PB
tree leaf extracts. In addition,
according to all of the investigated results and
properties of the Zinc Oxide Nanoparticles,
the Zinc Oxide Nanoparticles
that are
calcinated at
500 oC
had higher quality.
They performed better than those made
at other calcination temperatures.
REFERENCES
[1] Azeez
Abdullah Barzinjy, Samir Mustafa Hamad, Ahmed Fattah
Abdulrahman, Safiya Jameel Biro, and AbdulBasit Ali Ghafor, “Biosynthesis, Characterization and Mechanism of
Formation of ZnO Nanoparticles Using Petroselinum Crispum Leaf Extract”, Current Organic Synthesis, 2020, 17,
558-566. https://doi.org/10.2174/1570179417666200628140547.
[2] Abdelbaky, A.S.; Abd El-Mageed,
T.A.; Babalghith, A.O.; Selim, S.; Mohamed, A.M.H.A.
Green Synthesis and Characterization of ZnO
Nanoparticles Using Pelargonium odoratissimum (L.)
Aqueous Leaf Extract and Their Antioxidant, Antibacterial and
Anti-inflammatory Activities. Antioxidants 2022, 11, 1444.
[3] Khan,
I.; Saeed, K.; Khan, I. Nanoparticles: Properties applications and toxicities.
Arab. J. Chem. 2019, 12, 908–931.
[4] Nilavukkarasi, M.; Vijayakumar, S.; Prathipkumar,
S. Capparis zeylanica mediated bio-synthesized ZnO nanoparticles as antimicrobial photocatalytic and
anti-cancer applications. Mater. Sci. Technol. 2020, 3, 335–343.
[5] Zheng,
X.; Yuhui, W.; Ling, S.; Arunachalam, C.; Sulaiman, A.; Liwei, F. Anticarcinogenic effect of zinc
oxide nanoparticles synthesized from Rhizoma paridis saponins on Molt-4 leukemia cells. J. King Saud
Univ. Sci. 2020, 32, 1865–1871.
[6] A.
Waseem and K. Divya, “Green synthesis, characterization and anti-microbial
activities of ZnO nanoparticles using Euphorbia hirta leaf extract,” Journal of King Saud University
Science, vol. 32, no. 4, pp. 2358–2364, 2020.
[7] S.
Bettini, R. Pagano, V. Bonfrate, E. Maglie, D. Manno, A. Serra, L. Valli, G. Giancane, promising piezoelectric properties of new ZnO@ octadecylamine adduct, The
Journal of Physical Chemistry C 119(34) (2015) 20143-20149.
[8] H.
Hong, J. Shi, Y. Yang, Y. Zhang, J.W. Engle, R.J. Nickles,
X. Wang, W. Cai, Cancer-targeted optical imaging with fluorescent zinc oxide
nanowires, Nano letters 11(9) (2011) 3744-3750.
[9] Meron Girma Demissie, Fedlu Kedir Sabir, Gemechu Deressa Edossa, and Bedasa Abdisa Gonfa, Synthesis of Zinc
Oxide Nanoparticles Using Leaf Extract of Lippia adoensis (Koseret) and Evaluation
of Its Antibacterial Activity, Journal of Chemistry,
Vol.
2020, Article ID 7459042, 9 pages. https://doi.org/10.1155/2020/7459042
[10] M.
Seyyed, H. M. Tabrizi, E. Behrouz, and J. Vahid, “Biosynthesis of pure zinc
oxide nanoparticles using Quince seed mucilage for photocatalytic dye
degradation,” Journal of Alloys and Compounds, vol. 821, Article ID 153519,
2020.
[11] Karam,
S.T.; Abdulrahman, A.F. Green Synthesis and Characterization of ZnO Nanoparticles by Using Thyme Plant Leaf Extract.
Photonics 2022, 9, 594. https://doi.org/10.3390/photonics9080594.
[12] Amad Nori Abdulqudos, Ahmed
Fattah Abdulrahman, Biosynthesis and Characterization of ZnO
Nanoparticles by using Leaf Extraction of Allium Calocephalum
Wendelbow Plant, Passer 4 (Issue 2) (2022) 113-126. https://doi.org/10.24271/psr.2022.343112.1136.
[13] A.
J. Aswathy, T. R. Achuthsankar.
S. Nair. “Green synthesis and characterization of zinc oxide nanoparticles
using Cayratia pedata leaf
extract”, Biochemistry and Biophysics Reports,v ol. 26, pp. 100995, 2021.
[14]
A.A. Barzinjy, H. H. Azeez. “Green synthesis and
characterization of zinc oxide nanoparticles using Eucalyptus globulus Labill. leaf extract and zinc nitrate hexahydrate salt”, SN
Applied Sciences, vol. 2, no.99, 2020. https://doi.org/10.1007/s42452-020-2813-1.
[15] R.
Norouzi, M. Hejazy, and A. Ataei. “Scolicidal effect of zinc
oxide nanoparticles against hydatid cyst protoscolices
in vitro,” Nanomedicine Research Journal, vol. 4, no.1, pp. 23–28, 2019.
https://doi:10.22034/NMRJ.2019.01.004.
[16] V.
Srivastava, D. Gusain, and Y. C. Sharma. “Synthesi s, characterization and application of zinc oxide
nanoparticles (n-ZnO),” Ceramics International, vol.
39, no. 8, pp. 9803–9808, 2013. https://doi:10.1016/j.ceramint.2013.04.110.
[17] S.
Zandi, P. Kameli, H. Salamati, H. Ahmadvand, and M.
Hakimi. “Microstructure and optical properties of ZnO
nanoparticles prepared by a simple method,” Physica
B: Condensed Matter, vol. 406, no.17, pp. 3215–3218, 2011. https://doi:
10.1016/j.physb.2011.05.026.
[18] J.
P. Kim, I. K. Lee, B. S. Yun, S. H. Chung, G. S. Shim, H. Koshino,
I. D. Yoo. “Ellagic acid rhamnosides
from the stem bark of Eucalyptus globulus”, Phytochemistry, vol. 57,
pp.587–591, 2001.
[19] P.
Singh, Y. J. Kim, D. Zhang, D. C. Yang. “Biological synthesis of nanoparticles
from plants and microorganisms”, Trends Biotechnol,
vol. 34, pp.588–599. 2016.
[20] R.
Hocine, J. Mazauric, K. Madani, L. Boulekbache-Makhlouf.
“Phytochemical analysis and antioxidant activity of Eucalyptus globulus: a
comparative study between fruits and leaves extracts”, J. Chem. Eng Bio
Chemistry, vol. 1, pp.23–29, 2016.
[21] Pai, S.
Photocatalytic zinc oxide nanoparticles synthesis using Peltophorum
pterocarpum leaf extract and their characterization. Optik (Stuttg.), 2019, 185,
248-255.
http://dx.doi.org/10.1016/j.ijleo.2019.03.101
[22] Vidya,
C.; Hiremath, S.; Chandraprabha, M.N.; Antonyraj, M.L.; Gopal, I.V.; Jain, A.; Bansal, K. Green
synthesis of ZnO nanoparticles by Calotropis
gigantea. Int. J. Curr. Eng. Technol. 2013, 1,
118–120.
[23] Shim,
Y.J. Zinc oxide nanoparticles synthesized by Suaeda
japonica Makino and their photocatalytic degradation of methylene blue. Optik 2019, 182, 1015–1020.
[24] A.
Dey and S. Somaiah, “Green synthesis and
characterization of zinc oxide nanoparticles using leaf extract of Thryallis glauca (Cav.) Kuntze
and their role as antioxidant and antibacterial”, Microscopy Research and
Technique, April 2022, https://doi.org/10.1002/jemt.24132.
[25] A.
M. Abdo, A. Fouda, A. M. Eid, N. M. Fahmy, A. M. Elsayed, A. M. Khalil, O. M. Alzahrani,
A. F. Ahmed, A.M. Soliman. “Green Synthesis of Zinc Oxide Nanoparticles (ZnO-NPs) by Pseudomonas aeruginosa and Their Activity
against Pathogenic Microbes and Common House Mosquito, Culex pipiens”, Materials (Basel), vol. 14, no. 22, pp. 6983,
2021. https://doi:10.3390/ma14226983.
[26] S.
Abel, J. L. Tesfaye, R. Shanmugam, L. P. Dwarampudi,
G. Lamessa, N. Nagaprasad, M.Benti, R. Krishnaraj. "Green Synthesis and Characterizations of
Zinc Oxide (ZnO) Nanoparticles Using Aqueous Leaf
Extracts of Coffee (Coffea arabica) and Its Application in Environmental
Toxicity Reduction", J. of Nanomaterials, vol. 2021, ID 3413350, 6 pages,
2021. https://doi.org/10.1155/2021/3413350.
[27] A.
F. Abdulrahman. “The Influence of Various Reactants in the Growth Solution on
the Morphological and Structural Properties of ZnO
Nanorods”, Passer Journal, Vol. 2 (2), pp. 69-75, 2020. doi:
10.24271/psr.14.
[28] Korake, P.; Dhabbe, R.; Kadam,
A.; Gaikwad, Y.; Garadkar, K. Highly active lanthanum
doped ZnO nanorods for photodegradation of metasystox. J. Photochem. Photobiol. B Biol. 2014, 130, 11–19.
[29] A.
F. Abdulrahman, S. M. Ahmed, A. A. Barzinjy, S. M.
Hamad, N. M. Ahmed, M. A. Almessiere. “Fabrication
and Characterization of High-Quality UV Photodetectors Based ZnO Nanorods Using Traditional and Modified Chemical Bath
Deposition Methods”, Nanomaterials, vol. 11, no.3, pp. 677, 2021. https://doi.org/10.3390/nano11030677.
[30]
Ahmed F. Abdulrahman “The effect of different substrate-inclined angles on the
characteristic properties of ZnO nanorods for UV
photodetectors applications”, Journal of Materials Science: Materials in
Electronics, Vol.31 (17), 14357-14374, 2020.
[31]
Ahmed Fattah Abdulrahman, Sabah Mohammed Ahmed, Samir Mustafa Hamad, Azeez
Abdullah Barzinjy “Effect of Growth Temperature on
Morphological, Structural, and Optical Properties of ZnO
Nanorods Using Modified Chemical Bath Deposition Method”, Journal of Electronic
Materials, 50, 1482–1495 (2021).
[32] L. Roza, Y. A. Rahman, A. A. Umar, M. M. Salleh. “Direct
growth of oriented ZnO nanotubes by self-selective
etching at lower temperature for photo-electrochemical (PEC) solar cell
application”, J. of Alloys and Comps., vol. 618, pp.153, 2015.
[33] R. Shabannia, H.A. Hassan. “Characteristics of photoconductive
UV photodetector based on ZnO nanorods grown on
polyethylene naphthalate substrate by a chemical bath
deposition method”, Electron. Mater. Lett., vol. 10, pp.837–843, 2014.
https://doi.org/10.1007/s13391-014-3245-0.
[34] A. F.
Abdulrahman, N. M. Abd-Alghafour.“Synthesis
and characterization of ZnO nanoflowers by using
simple spray pyrolysis technique”, Solid-State Electronics, vol. 189,
pp.108225, 2022. https://doi.org/10.1016/j.sse.2021.108225.
[35] M. M.
Khan. “Potentials of Costus woodsonii
leaf extract in producing narrow band gap ZnO
nanoparticles”, Material Science Semicondutor
Process., vol. 91, pp. 194200, 2019.
[35] Kamal K. Taha; M. Al Zoman; M. Al Outeibi; S. Alhussain; A. Modwi; Abdulaziz A. Bagabas; "Green
and Sonogreen Synthesis of Zinc Oxide Nanoparticles
for The Photocatalytic Degradation of Methylene Blue in Water",
NANOTECHNOLOGY FOR ENVIRONMENTAL ENGINEERING, 2019. (IF:
3)
[36] Happy Agarwal; Amatullah Nakara; Soumya Menon; VenkatKumar Shanmugam; "Eco-friendly
Synthesis of Zinc Oxide Nanoparticles Using Cinnamomum Tamala Leaf Extract and
Its Promising Effect Towards The Antibacterial Activity",
JOURNAL OF DRUG DELIVERY SCIENCE AND
TECHNOLOGY, 2019. (IF: 3)
[37] Aravapalli Vanaja; M. Suresh; Jaison Jeevanandam; Venkatesh; Sk. Gousia; D. Pavan; D. Balaji; N. Bhanu
Murthy; "Copper-Doped
Zinc Oxide Nanoparticles for The Fabrication of White LEDs",
PROTECTION OF METALS AND PHYSICAL CHEMISTRY OF SURFACES, 2019.
[38] K Kanimozhi; S Khaleel
Basha; K Kaviyarasu; V SuganthaKumari; "Salt
Leaching Synthesis, Characterization and In Vitro Cytocompatibility of
Chitosan/Poly(vinyl Alcohol)/Methylcellulose - ZnO
Nanocomposites Scaffolds Using L929 Fibroblast Cells",
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY, 2019. (IF: 3)
[39] Geeta Gahlawat; Anirban Roy
Choudhury; "A
Review on The Biosynthesis of Metal and Metal Salt Nanoparticles By
Microbes",
RSC ADVANCES, 2019. (IF: 5)
[40] Wencai Zhou; Xueying Qiu; Yuheng Jiang; Yingying Fan; Shilei Wei; Dongxue Han; Li Niu; Zhiyong Tang; "Highly
Selective Aerobic Oxidation of Methane to Methanol Over Gold Decorated Zinc
Oxide Via Photocatalysis",
JOURNAL OF MATERIALS CHEMISTRY, 2020. (IF: 3)
[41] Shriniwas P. Patil; Subhash T. Kumbhar; "Vitex
Negundo Assisted Green Synthesis of Metallic Nanoparticles with Different
Applications: A Mini Review",
FUTURE JOURNAL OF PHARMACEUTICAL SCIENCES, 2020.
[42] Amit Kumar
Chauhan; Navish Kataria; V K Garg; "Green
Fabrication Of ZnO Nanoparticles Using Eucalyptus
Spp. Leaves Extract And Their Application In Wastewater Remediation",
CHEMOSPHERE, 2020. (IF: 3)
[43] Anithadevi Sekar; Rakhi Yadav; "Green
Fabrication of Zinc Oxide Supported Carbon Dots for Visible Light-Responsive
Photocatalytic Decolourization of Malachite Green
Dye: Optimization and Kinetic Studies",
OPTIK, 2021.
[44] Ashmalina Rahman; Mohammad Hilni Harunsani; Ai Ling Tan; Mohammad Mansoob Khan; "Zinc
Oxide and Zinc Oxide-based Nanostructures: Biogenic and Phytogenic Synthesis,
Properties and Applications",
BIOPROCESS AND BIOSYSTEMS ENGINEERING, 2021.
[45] Gezahegn Faye; Tola Jebessa; Tilahun Wubalem; "Biosynthesis,
Characterisation and Antimicrobial Activity of Zinc
Oxide and Nickel Doped Zinc Oxide Nanoparticles Using Euphorbia Abyssinica Bark Extract",
IET NANOBIOTECHNOLOGY, 2021.
[46] Hadiza Abdullahi
Ari; Alani Olushola Adewole; Adamu Yunusa Ugya; Otaru Habiba Asipita; Makiyyu Abdullahi
Musa; Wei Feng; "Biogenic
Fabrication and Enhanced Photocatalytic Degradation of Tetracycline By Bio
Structured ZnO Nanoparticles",
ENVIRONMENTAL TECHNOLOGY, 2021.
[47] Amany M Diab; Basma T Shokr; Mustafa Shukry; Foad A Farrag; Radi A Mohamed; "Effects
of Dietary Supplementation with Green-Synthesized Zinc Oxide Nanoparticles for
Candidiasis Control in Oreochromis Niloticus",
BIOLOGICAL TRACE ELEMENT RESEARCH, 2022.
[48] Ibrahem M A Hasan; Ahmed R
Tawfik; Fawzy H Assaf; "GC/MS
Screening of Buckthorn Phytochemicals and Their Use to Synthesize ZnO Nanoparticles for Photocatalytic Degradation of
Malachite Green Dye in Water",
WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON
WATER POLLUTION RESEARCH, 2022.
[49] Muhammad
Irfan; Hira Munir; Hammad Ismail; "Characterization
and Fabrication of Zinc Oxide Nanoparticles By Gum Acacia Modesta
Through Green Chemistry and Impregnation on Surgical Sutures to Boost Up The
Wound Healing Process",
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES, 2022.
[50] Senthilkumar
Chandrasekaran; Venkattappan Anbazhagan; Shanmugam Anusuya; "Green
Route Synthesis of ZnO Nanoparticles Using Senna
Auriculata Aqueous Flower Extract As Reducing Agent and Evaluation of Its
Antimicrobial, Antidiabetic and Cytotoxic Activity",
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY, 2022.
[51] Rahul Nitnavare; Joorie Bhattacharya; Sirikanjana Thongmee; Sougata Ghosh; "Photosynthetic
Microbes in Nanobiotechnology: Applications and Perspectives",
THE SCIENCE OF THE TOTAL ENVIRONMENT, 2022.
[52] Selvakumar Sakthivel; Anand Raj Dhanapal; Lilly Pushpa
Paulraj; Annadurai Gurusamy; Baskar Venkidasamy; Muthu Thiruvengadam; Rajakumar Govindasamy; Mohammad Ali
Shariati; Abdelhakim Bouyahya; Gokhan Zengin; Mohammad
Mehedi Hasan; Pavel Burkov; "Antibacterial
Activity of Seed Aqueous Extract of Citrus Limon (L.) Mediated Synthesis ZnO NPs: An Impact on Zebrafish ( Danio Rerio ) Caudal Fin
Development",
HELIYON, 2022.
[53] Dorcas Mutukwa; Raymond Taziwa; Lindiwe
Eudora Khotseng; "A
Review of The Green Synthesis of ZnO Nanoparticles Utilising Southern African Indigenous Medicinal
Plants", Nanomaterials
(Basel, Switzerland), 2022.
[54] Shahid
Shabbir Awan; Rizwan Taj
Khan; Ansar Mehmood; Muhammad
Hafeez; Syed Rizwan Abass; Munazza Nazir; Muhammad
Raffi; "Ailanthus
Altissima Leaf Extract Mediated Green Production of
Zinc Oxide (ZnO) Nanoparticles for Antibacterial and
Antioxidant Activity",
Saudi Journal Of
Biological Sciences, 2022.