We provide the first experimental evidence of oxygen vacancy defect induced ferromagnetism in undoped multiferroic CaMn7O12 (CMO) manganite synthesized from the facile chemical combustion method. The ...obtained nanocrystalline is characterized by various techniques like TGA, FTIR, XRD, SEM-EDX, AFM, UV-visible, XPS, and SQUID, etc. to confirm the phase purity and crystallinity of CMO. Surface roughness increases with sintering time attributed to the increase of surface oxygen vacancy defects. X-ray photoelectron spectroscopy was carried out to confirm the oxidation state of constituent elements and also provides direct evidence of enhanced oxygen vacancies. UV–vis optical absorption used to infer band gap shift from 1.68 to 1.38 eV, respectively, is also attributed to increases in oxygen vacancy defects. Multiple magnetic phase transition temperatures of 90, 50, and 42 K, respectively, were obtained from the derivative of magnetization. A systematic decrease of full widths at half maxima (fwhm) of dM/dT vs T curves with sintering time indicates strengthening of ferromagnetism (FM). Transition temperature does not change significantly with sintering time, indicating the extrinsic origin of FM. The results of the UV–vis, XPS, and AFM and strengthening of ferromagnetism all are corroborated with each other’s results and also attribute to enhanced oxygen vacancy concentration with sintering time. The origin of FM in undoped CMO manganite with sintering time results from bound magnetic polarons (BMPs) of enhanced iterant and the localized electron of oxygen vacancies trapped center at the surface or interfaces. Our finding also opens a new perspective for exploiting oxygen vacancy defect engineering at surfaces or interfaces in the design of exotic magnetic- and spintronics-based devices.
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IJS, KILJ, NUK, PNG, UL, UM
The development and characterization of an organic thin-film diode based on herbal dyes has been presented. The electronic parameters of the diode are retrieved using a thermionic emission approach ...from the I-V characteristics. Furthermore, the computed values of ideality factor (n), barrier height (ϕ) and series resistance (Rs) of Al/Beetroot/Cu using the Cheung and Cheung functions are 4.5, 0.73 eV and 1.10 KΩ, respectively. The values of Rs in these two different approaches are very similar, but a discrepancy in values of n confirms the existence of high Rs and high interface state density. The band gap of betanin and temperature dependence of n, ϕ, and Rs confirm the semiconducting behaviour of beet root. We observed a linear relationship between ϕ and 1/n for Al/Beetroot/Cu, confirming that the device is a Schottky diode. The fact that quantum tunneling plays a significant role in the charge conduction procedure with thermionic emission is confirmed by the parabolic conductance of Al/Beetroot/Cu. We have identified that Schottky emission dominates Poole-Frenkle emission for the Al/Beetroot/Cu diode based on both theoretical and experimental values of β. The G(V) vs V plot was used to explain the existence of the reported dye's trapping effect. We also calculated the device's trap energy (Ec), which is substantially lower than previously reported organic diodes. The theoretically estimated value of the insulating temperature for Al/Beetroot/Cu is 133 K. When we utilise beetroot dye instead of indigo dye, the value of n and Rs decreases from 11.65 to 4.5 and 430 KΩ to 1.1 KΩ, respectively, according to the comparison analysis. The trap energy drops from 0.0732 to 0.021 eV once more.
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•The electronic parameters of the diode are retrieved using thermionic emission approach from the I-V characteristics and using Cheung and Cheung function.•Semiconducting behaviour of beet root is confirmed by the band gap and temperature dependence of Rs.•We observed a linear relationship between ϕ and 1/n, for Al/Beet/Cu confirming that the device is a Schottky diode.•The fact that quantum tunneling plays a significant role in the current conduction process with thermionic emission is confirmed by the Parabolic conductance of Al/Beet/Cu.•When we utilise beetroot dye instead of indigo dye, the value of n and Rs decreases from 11.65 to 4.5 and 430 KΩ to 1.1 KΩ, respectively. The trap energy drops from 0.0732 to 0.021 eV once more.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In the present study, a total of 53 promising salt-tolerant genotypes were tested across 18 salt-affected diverse locations for three years. An attempt was made to identify ideal test locations and ...mega-environments using GGE biplot analysis. The CSSRI sodic environment was the most discriminating location in individual years as well as over the years and could be used to screen out unstable and salt-sensitive genotypes. Genotypes CSR36, CSR-2K-219, and CSR-2K-262 were found ideal across years. Overall, Genotypes CSR-2K-219, CSR-2K-262, and CSR-2K-242 were found superior and stable among all genotypes with higher mean yields. Different sets of genotypes emerged as winners in saline soils but not in sodic soils; however, Genotype CSR-2K-262 was the only genotype that was best under both saline and alkaline environments over the years. The lack of repeatable associations among locations and repeatable mega-environment groupings indicated the complexity of soil salinity. Hence, a multi-location and multi-year evaluation is indispensable for evaluating the test sites as well as identifying genotypes with consistently specific and wider adaptation to particular agro-climatic zones. The genotypes identified in the present study could be used for commercial cultivation across edaphically challenged areas for sustainable production.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In this paper, we investigate the dark energy phenomenon by studying the Tsallis holographic dark energy within the framework of Brans–Dicke (BD) scalar–tensor theory of gravity (Brans and Dicke in ...Phys. Rev. 124:925, 1961). In this context, we choose the BD scalar field
ϕ
as a logarithmic function of the average scale factor
a
(
t
) and Hubble horizon as the IR cutoff (
L
=
H
-
1
). We reconstruct two cases of non-interacting and interacting fluid (dark sectors of cosmos) scenario. The physical behavior of the models are discussed with the help of graphical representation to explore the accelerated expansion of the universe. Moreover, the stability of the models are checked through squared sound speed
v
s
2
. The well-known cosmological plane i.e.,
ω
de
-
ω
de
′
is constructed for our models. We also include comparison of our findings of these dynamical parameters with observational constraints. It is also quite interesting to mention here that the results of deceleration, equation of state parameters and
ω
de
-
ω
de
′
plane coincide with the modern observational data.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Currently, enhancing the performance of electrochemical supercapacitors is the subject of intense research to fulfill the ever-increasing demand for grid-scale energy storage and delivery solution, ...thereby utilizing the full potential of renewable energy resources and decreasing our dependence on fossil fuels. Metal sulfides, such as cobalt sulfide (CoS), nickel sulfide (NiS), molybdenum sulfide (MoS), copper sulfide (CuS), and others, have recently emerged as a promising class of active electrode materials, alongside other supercapacitor electrode materials, due to their relatively high specific capacitance values and exceptional reversible redox reaction activities. The synthesis, characterizations, and electrochemical performances of single-phase nanocrystalline β-NiS are presented here and the electrode based on this material shows a specific capacitance of 1578 F g
−1
at 1 A g
−1
from the galvanostatic discharge profile, whereas a capacitance of 1611 F g
−1
at 1 mV s
−1
was obtained through the CV curve in 2 M KOH aqueous electrolyte. Additionally, the electrode also performs well in neutral 0.5 M Na
2
SO
4
electrolytes resulting in specific capacitance equivalent to 403 F g
−1
at 1 mV s
−1
scan rate. The high charge storage capacity of the material is due to the superior intercalative (inner) charge storage coupled with the surface (outer) charges stored by the β-NiS electrode and was found to be 72% and 28%, respectively, in aqueous 2 M KOH electrolyte. This intercalative charge storage mechanism is also responsible for its excellent cycling stability. Additionally, we assembled aqueous asymmetric supercapacitors (ASCs) with activated carbon (AC) as the negative electrode and the β-NiS electrode as the positive electrode. The combination of the β-NiS electrode and AC with excellent cycling stability resulted in the highest specific energy equivalent to ∼163 W h kg
−1
and a specific power of ∼507 W kg
−1
at 1 A g
−1
current rate.
The high charge storage capacity (1578 F g
−1
at 1 A g
−1
) of β-NiS electrode is due to the superior intercalative (inner) charge storage coupled with the surface (outer) charges stored by the single phase β-NiS electrode.
The Scaps-1d simulator was used to simulate a lead-free perovskite CH
3
NH
3
SnI
3
based solar cell devices fabricated from different hole transport materials (HTM). This research looks at two ...organic and two inorganic HTM layers. The cell structure used in this study is FTO/TiO
2
/CH
3
NH
3
SnI
3
/HTM (variable)/Au(variable). Spiro-OMeTAD, PEDOT:PSS, CuO and Cu
2
O are the HTM materials used. The results show that utilizing CuO as an HTM produces better outcomes than other HTMs, with an efficiency of 28.45%. The thickness, acceptor concentration (N
A
), and defect density (N
t
) of the perovskite layer on optoelectronic properties of the solar cell are focus of simulation studies. According to this study, an perovskite layer thickness of 1000 nm is suitable for a decent photovoltaic cell. Furthermore, by adjusting the HTM thickness and the defect density of HTM and absorber layer, promising findings of J
sc
of 34.38 mAcm
−2
, V
oc
of 1.011 V, FF of 80.85% and PCE of 28.10% were obtained for Spiro-OMeTAD based PSC. Finally, in order to improve the device's performance, an anode material with high work function is required. Our findings reveal that using a thin absorber layer results in low photo generated charge carriers due to less absorption, but high carrier extraction. Although more carriers are created in the cell due to increased absorption, decreased collection efficiency is related to recombination, which decreases V
oc
for thick perovskite layers. Device efficiency is improved by increasing the doping density up to 10
18
cm
−3
in the perovskite layer due to built-in electric field across the solar cell. Again a very thin or thick HTL is not ideal for high PCE. For low recombination and a high fill factor, an HTM (Spiro-OMeTAD) of 1–100 nm is necessary. The great power conversion efficiency of organic HTM based lead-free PSC brings up the new possibilities for obtaining renewable energy.
In this report, we have used cylindrical and spherical zinc oxide (ZnO) nanoparticles to fabricate FTO/ZnO/Al and herbal dye-based FTO/Beet + ZnO/Al Schottky diodes. Electrical parameters of the ...reported organic Schottky diode have been measured in different methods to analyse the effect of ZnO nano morphology on the device performance. These approaches were found to be remarkably consistent with one another. The calculated values of the FTO/Beetroot/Al series resistance (
R
s
), barrier height (
n
), trap energy (
E
c
), and ideality factor (
n
) are 1.77, 0.65 eV, 0.052 eV, and 589, respectively. These values change to 1.7, 0.62 eV, 0.048 eV, and 61, respectively, after the inclusion of cylindrical ZnO with beetroot dye. The values of
n
and
R
s
drop from 1.7 to 1.4 and 61 to 52 correspondingly when spherical ZnO nanoparticles are used in place of cylindrical ZnO. Again, reduction of trap energy of the reported organic Schottky diode is much higher in presence of Spherical ZnO than cylindrical ZnO. Series resistance (
R
s
), trap energy (
E
t
), and barrier height (ϕ) have all decreased, respectively, by 91%, 11.5%, and 8%. Using spherical ZnO instead of cylindrical ZnO results in a 17% greater reduction in
R
s
. The disclosed devices' mobility and current conductivity are enhanced by this lowering. In this article, the used ZnO nanoparticles are not spherically perfect; if they were, this increase would be more apparent.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The electrical parameters like barrier height (
ϕ
), series resistance (
R
s
), threshold voltage (
V
th
) and trap energy (
E
c
) of a herbal dye-based organic Schottky diode were investigated. ...Improvement in the outcome of the aforementioned parameters were investigated in the presence of zinc oxide (ZnO) nanoparticles. It has been observed that the preceding characteristics were likewise affected by ZnO nanoparticles. It has been calculated and shown that the incorporation of ZnO nanoparticles lowered the
ϕ
of Al/Beet/Cu from 0.75 to 0.73 eV based on
I–V
characteristics. Analysis of the outcome by using Norde function shows the barrier height reduction from 0.78 to 0.75 eV for the same experiment. Hence, the results produced using two above-mentioned methodologies are in good agreement together. The incorporation of ZnO nanoparticles reduces trap energy and series resistance by 36.98 and 23.81%, respectively, improving current conduction in the bulk regime and lowering the Schottky diode’s threshold voltage (
V
th
) from 0.74 to 0.45 V. The impact of ZnO nanoparticles on a variety of natural dyes, such as turmeric and indigo, has also been studied. Validation of the results for experimental dyes reveals a wider range of relevance for the current study.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Calf diarrhoea remains the biggest challenge both in the small and large farms. Infectious diarrhoea is associated with many pathogens,
Escherichia coli
being one, but majority are systematically ...treated with antibiotics. Since antimicrobial resistance (AMR) is a growing menace, the need to find alternative prophylactic solutions using popular kitchen herbs such as
Trachyspermum ammi
(carom seeds),
Curcuma longa
(turmeric) and cinnamon (
Cinnamomum
sp.) extracts is been investigated against virulent form of
E. coli
isolated from calf diarrhoea. The virulence factors identified in these isolates were ST (32.5%), LT (20%),
eaeA
(15%),
stx1
(2.5%) and
stx2
(5%) with the occurrence of the most common serogroups as O18 (15%) followed by O111 (12.5%). Highest resistance was seen with beta lactam + beta lactamase inhibitor (amoxicillin/clavulanic acid) followed by beta lactams (ampicillin, cefuroxime and cefepime). The zone of inhibition due to cinnamon (methanol) and carom seed (ethanol) extracts (500 to 250 μg/mL concentration) on
E. coli
bacteria was >19 mm, respectively. Turmeric, cinnamon and carom had the potency of inhibiting the pathogenic
E. coli
which maybe suggestive of its use in calf diets as prophylaxis against diarrhoea.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Grid-scale energy storage solutions are necessary for using renewable energy sources efficiently. A supercapattery (supercapacitor + battery) has recently been introduced as a new variety of hybrid ...devices that engage both capacitive and faradaic charge storage processes. Nano-chain architectures of Ni
Co
S electrode materials consisting of interconnected nano-spheres are rationally constructed by tailoring the surface structure. Nano-chains of the bimetallic sulfide Ni
Co
S are presented to have a superior charge storage capacity. The Ni
Co
S nano-chain electrode presents a capacitance of 2001.6 F g
at 1 mV s
, with a specific capacity of 267 mA h g
(1920 F g
) at 1 A g
in 4 M KOH aqueous electrolyte through the galvanostatic charge-discharge (GCD) method. The reason behind the high charge storage capacity of the materials is the predominant redox-mediated diffusion-controlled pseudocapacitive mechanism coupled with surface capacitance (electrosorption), as the surface (outer) and intercalative (inner) charges stored by the Ni
Co
S electrodes are close to 46.0% and 54.0%, respectively. Additionally, a Ni
Co
S//AC two electrode full cell operating in asymmetric supercapacitor cell (ASCs) mode in 4 M KOH electrolyte exhibits an impressive energy density equivalent to 257 W h kg
and a power density of 0.73 kW kg
at a current rate of 1 A g
.
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