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Electrochemical Oxidation of Methanol at Pt/Au Modified
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To find a novel and a cheap anode for direct methanol fuel cell that resists the poisoning by carbon monoxide
produced inside the cell Methods/Statistical Analysis: We prepare triplet electrode by using electrodeposition technique
in nano-scale to improve the overall electro-catalytic properties of anode towards electrochemical oxidation of methanol
Findings: The prepared nano-anode is better than the traditional electrode Pt/Au because the triplet anode Pt/Au/Sn give
higher current density in low over potential Application/Improvements: There exist many applications of this triplet
nano-anode in portable devices, cars, vehicles, airplanes and space shuttles
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Controlled Hydrothermal Synthesis of NanoMoO2 as Anode for Lithium Ion Battery
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Nano-MoO2, with different allotropic forms is
synthesized through a reduction reaction of molybdenum trioxide
in aqueous solutions using ethylene glycol The structure and
morphology characterizations are carried out by XRD, SEM, and
Raman The XRD and SEM data indicate the as-prepared samples
present a single and homogeneous phase MoO2 with monocline
symmetry Findings/application: The optical properties of the
as-synthesized samples are investigated by photoluminescence
Cyclic voltammetric characterization of MoO2 films has revealed
reversible redox behavior with charge–discharge cycling which
corresponds to the reversible lithium intercalation/deintercalation
The electrochemical properties study of the MoO2 has showed that
the monoclinic MoO2 has a good stability and a nice reversibility,
an indicator that the molybdenum dioxide is most suitable for
application in lithium-ion batteries (LIBs)
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Enhanced solar photocatalytic performance of Cu-doped nanosized ZnO
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We report the controlled synthesis of nanostructured undoped and Cu-doped ZnO by a simple one-step
hydrothermal treatment, characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM),
Raman spectroscopy and photoluminescence (PL) XRD results showed that all samples present a hexagonal
wurtzite structure The SEM micrographs revealed that the particles have a hexagonal shape and a
uniform size distribution Optical band gap was found to vary with Cu content The photoluminescence
spectra indicate that the introduction of Cu into pure nano-ZnO causes a decrease in surface defects, such
as oxygen and zinc vacancy In fact, this study shows that the intensity of the PL decreases initially when
the concentration of Cu doping increases (greater than 1%) Whereas, when the concentration of the Cu
doping rate is 05% the PL intensity increases The result indicates that doping with Cu with a suitable
concentration can effectively inhibit the recombination of the free charge carriers The as-synthesized
nanostructures were used as photocatalysts for the degradation of methyl orange (MO) under solar irradiation
The PL and photocatalysis results reveal that the highest photocatalytic activity is obtained with
the 1% Cu-doped ZnO photocatalyst In fact, this study shows that the photodegradation follows firstorder
kinetics Therefore, in the absence of ZnO photocatalyst a low kinetic rate constant of 5634104-
min1 is estimated while the introduction of undoped or 1% Cu-doped ZnO increases the kinetic constant
by approximately 9 and 20 times, respectively
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Pulsating flow of nanofluid with shape effects of particles on the cooling efficiency of photovoltaic panel and performance estimations with machine learning approaches
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The present work proposes a new cooling system for thermal management and cooling of
photovoltaic (PV) systems Pulsating flow with multiple jet impingement is considered by using
different fluid types Hybrid nanofluid and alumina–water nanofluid having cylindrical ans
spherical shaped nanoparticles are used as the cooling medium The study is conducted by using
finite volume method for various values of pulsating amplitude (between 0 and 1), Strouhal
number (between 001 and 1), solid volume fraction of nanoparticles (between 0 and 2%) and
slot number of the impinging jet (between 1 and 13) It is observed that pulsating amplitude
is more effective on the cooling performance enhancement as compared to frequency while
average Nusselt number (Nu) rises by about 635% while temperature drop of 216 ◦C can
be achieved when pulsation amplitude is increased from 0 to 1 Nanofluid with cylindrical
shaped nanoparticles and hybrid nanofluid show very similar trends while temperature drop
of 26 ◦C is achieved when cooling system with nanofluid-cylinder in pulsating flow case is
compared with pure-fluid in non-pulsating flow configuration When nanoparticles loading
amount on the thermal improvement is compared, the most favorable cases are obtained
for nanofluid-cylinder and hybrid nanofluid case The average Nu increments become 35%,
228% and 229% for nanofluid-spherical, nanofluid-cylinder and hybrid nanofluid when lowest
and highest nanoparticle loading amount cases are compared Increasing the slot number in
pulsating flow case significantly rises the Nu and drops the average panel surface temperature
When different systems are compared pulsating nano-jets cooling system using alumina–water
nanofluid with cylindrical shaped nanoparticles provides the most effective cooling system while
while temperature drop of 𝛥𝑇 = 3730 ◦C is achieved at the highest amplitude and highest
loading of nanoparticles in the pure fluid as compared to uncooled PV system
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Novel composite materials H2V3O8/PEDOT:PSS as cathode for rechargeable lithium ion batteries
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Owing to the high demand for electronic devices and electric vehicles, a huge effort
has been directed to the exploration and development of new batteries with good
cycling stability, satisfactory high specific capacity and safety In this paper,we report
the designed synthesis of the vanadium oxide with mixed valence H2V3O8 and the
composite H2V3O8/PEDOT:PSS using low cost and easy hydrothermal method
Electrochemical activity of the vanadium oxyhydroxide H2V3O8 and the composite
H2V3O8/PEDOT:PSS as cathodes materials for high performance lithium–ion batterieswasevaluated
vsLi?/Li at various current ratesComparedwith pureH2V3O8,
composite H2V3O8/PEDOT:PSS cathode exhibits higher specific capacity
(390 mAh g-1 at 005 A g-1 whereas, an initial discharge capacity of 300 mAh g-1 is
observed at 03 A g-1), more excellent rate performance and longer cycle life The
composite H2V3O8/PEDOT:PSS cathode delivers excellent specific capacity of ca
390 mAh g-1 and a 975% capacity retention are achieved even after 350 cycles at
current density of 005 A g-1 Higher electrochemical capacity and stability of the
new composite cathode are mainly ascribed to a cooperative effect between the
conductive polymer (PEDOT:PSS) with good electrical conductivity and the unique
nano-sized H2V3O8 rods with short diffusion pathway for lithium ions diffusion
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Enhanced photocatalytic properties of nano-Nb2O5 for degradation of methylene blue
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Mixing the advantages of nano-Nb2O5 and reduced graphene oxide (rGO), composite systems offer great potential of exploration Herein, Nb2O5 nanoparticles (NPs) and Nb2O5 modified reduced graphene oxide (Nb2O5/rGO) urchin-like have been successfully synthesized by hydrothermal process The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, nitrogen adsorption-desorption isotherms, and UV–vis diffuse reflectance spectroscopy The photocatalytic efficiency of the Nb2O5 NPs and Nb2O5/rGO urchin-like were evaluated with respect to the degradation of methylene blue (MB) under solar radiation It is found that the Nb2O5/rGO with porous structure and high specific surface area of ~10525 m2/g shows significantly superior photocatalytic performances for the removal of the MB dye (99% degradation after 1h illumination) than pure Nb2O5 (20% degradation after 1h illumination) The improvement in the photocatalytic properties of the composite material is mainly ascribed to a cooperative effect between the rGO with good electrical conductivity and the unique nano-porous structure of Nb2O5 with abundant catalytic active sites, superior charge transfer efficiency, and stronger oxidation property
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