Photocatalysts have been considered as a possible economical

i need to write a literature view for my phd thesis about aluminium nanoparticles and its mechanism and effect on photocatalysis using articles below

LITERATURE REVIEW
Photocatalysts have been considered as a possible
economical approach for addressing various energy
and environment related challenges. With the
advanced development of nanometer photocatalytic
oxidation technology, new ways can now be created
to solve the rising serious environmental pollution
issues such as soil, air, and water. On the other hand,
nanoparticle research has become an area of a great
scientific interest due to many possible applications
in electronic, biomedical, and optical fields. For the
last one decade, aluminum nanoparticles have been
intensely researched and used mainly because of their
higher reactivity than traditional micron-sized
particles. Aluminum is a block P, Period 3, group 13
element. The morphology of aluminum Nano-
particles is spherical which appear as grey-black or
black powder. Aluminum makes up about 8% of the
Earth’s crust. Aluminum is the third most abundant
element on earth after silicon and oxygen and the
most abundant metal in the earth crust. Aluminum
metal is very reactive and thus exists a wide range of
compounds. It is found combined in more than 270
different minerals.
Thermal annealing is commonly used in optical
applications, which play critical role in enhancing the
properties of the film [6]. Zhao et al [6] investigated
optical and structural properties of Aluminum oxide
thin films especially in the annealing range of 200 to
900o C. Temperature greatly influences the film
structure and optical properties. The studied showed
that for film annealed at low temperature to above
600 oC, the film optical properties including optical
constants and transmittance can be enhanced through
thermal annealing with amorphous structure as well
as smooth surface. But film annealed at extreme
temperature of 900 oC, results in the poor
performance of optical properties hence not suitable
in use for optics applications because of notable
changes in both surface texture and structure. At 600
oC, the transmittance of aluminum oxide is at
maximum, with improved refractive index [6].
Aluminum nanoparticles are impeccable catalysts for
many chemical reactions. Aluminum nanoparticles
are added to solid rocket fuel to enhance the speed of
combustion and sizably increase heat and stability of
combustion. Most importantly, aluminum
nanoparticles can be used in photocatalysts
application. Aluminum oxide nanoparticles have
become a hot topic with many researchers
investigating due to its wider range of application in
various field.
Photocatalysis continues to be one of widely studied
field due to its many possible applications. The
photocatalytic detoxification of wastewater by the
use of both heterogeneous catalysis and solar
technologies [1]. Various photocatalytic materials
including ZnO, CdS, TiO2, Fe2O3 and CuO have
been used effectively to degrade various dyes.
Aluminum nanoparticles can be doped with
photocatalytics elements to enhance the
photocatalytic activity. Zhang et al [4] found that
when zinc oxide based photactalytic activity can be
enhanced greatly by doping it with aluminum. This
has showed great photocatalytic activities, many
times more efficient that before. Nanoparticles with
about 20% Aluminum exhibit great absorption
capacity thus can significantly reduce the
concentration of methyl orange from 200 to 2.7
mg/L and photograde further Methyl Orange within
thirty minutes irradiation. Luo et al [2] studied the
influence of various aluminum slats on the
photocatalytic properties of Al dopes TiO2
nanoparticles towards dye degradation. Based on
1

their photocatalytic tests, Al-TiO2 nanoparticles
exhibits superior photocatalytic activity especially for
the decomposition of dye.
Various aluminum slats have non-negligible effect on
the surface morphology, grain size, structure, phase
purity as well as photocatalytic properties. The
nanoparticles sizes in pure TiO2 increases and
apparent adhesion and agglomeration take places
with calcination temperature increase. The addition
of Al in photocatalytic materials hinders grain
agglomeration and growth, hence resulting in the
crystallite size of anatase shrinking, improving phase
purity as well as increasing the transformation
temperature of anatase to rutile, which enhances
photocatalitic activity [2]. Aluminum doping reduces
the energy gap of Al-TiO2. Best on the study, Al-
TiO2 nanoparticles shows superior photocatalytic
activity for AO& dye decomposition.
The effectiveness of photocatalytic processes is
influence largely by plasmonic materials, which can
improve the absorption of light and energy
conversion efficiency. Aluminum acts as an
alternative plasmonic material with an increase
response into the deep UV region (Hao et al., [3]. The
extended response alongside the cost effectiveness
and opportune manufacturing makes aluminum
suitable in UV plasmonics application including
surface-enhanced fluorescence and Raman scattering
as well as photovoltaics. Aluminum exhibits high-
performance photo-catalysis.
According to Areerachakul et al. [8], compared the
performance of pure TiO2 and TiO2 doped with
aluminum on the photocatalysis process. The study
found that al-doped TiO2 could be used as
aphotocatalyst for organic pollutant degradation from
wastewater under the visible light irradiation. With
TiO2 alone only 75% of the organic pollutants
removal was achieved. With TiO2 doped with
aluminum, the value increase to 80% [8]. Similar
results was noted by Mahdavi & Talesh (2017) that
showed that 5-percent of AZO–RGO nanoparticles
has a higher efficiency than pure ZnO and ZnO–RGO
samples in the photoocatalytic process. This enhance
activity observed with the addition of aluminum
might be linked to synergetic effects of Al dopants.
References
[1]D. Pathania, R. Katwal and H. Kaur, "Enhanced
photocatalytic activity of electrochemically
synthesized aluminum oxide nanoparticles",
International Journal of Minerals, Metallurgy, and
Materials, vol. 23, no. 3, pp. 358-371, 2016.
Available: 10.1007/s12613-016-1245-9.
[2]J. Luo et al., "Influence of different aluminum
salts on the photocatalytic properties of Al doped
TiO2 nanoparticles towards the degradation of AO7
dye", Scientific Reports, vol. 7, no. 1, 2017.
Available: 10.1038/s41598-017-08216-2.
[3]Q. Hao et al., "Aluminum plasmonic
photocatalysis", Scientific Reports, vol. 5, no. 1,
2015. Available: 10.1038/srep15288.
[4]X. Zhang, Y. Chen, S. Zhang and C. Qiu, "High
photocatalytic performance of high concentration Al-
doped ZnO nanoparticles", Separation and
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2017. Available: 10.1016/j.seppur.2016.08.016.
[5]S. Khayatian, A. Kompany, N. Shahtahmassebi
and A. Khorsand Zak, "Enhanced Photocatalytic
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Graphene Oxide Nanocomposite for Removing of
Methyl Orange Dye from Water Under Visible-Light
Irradiation", Journal of Inorganic and
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6, pp. 2677-2688, 2018. Available: 10.1007/s10904-
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[7]R. Mahdavi and S. Talesh, "Sol-gel synthesis,
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of Al doped ZnO nanoparticles", Advanced Powder
Technology, vol. 28, no. 5, pp. 1418-1425, 2017.
Available: 10.1016/j.apt.2017.03.014.
[6]Z. Zhao, B. Tay, L. Huang, S. Lau and J. Gao,
"Influence of thermal annealing on optical properties
and structure of aluminium oxide thin films by
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27, no. 3, pp. 465-469, 2004. Available:
10.1016/j.optmat.2004.03.027.
[8]N. Areerachakul, S. Sakulkhaemaruethai, M.
Johir, J. Kandasamy and S. Vigneswaran,
"Photocatalytic degradation of organic pollutants
from wastewater using aluminium doped titanium
dioxide", Journal of Water Process Engineering, vol.
27, pp. 177-184, 2019. Available:
10.1016/j.jwpe.2018.12.006.