We report a green route method for the effective reduction of graphene oxide using Cinnamon extract. ZrO
2
nanomaterial synthesized
via
facile green induced method and zirconia-reduced graphene oxide ...nanocomposite (NC) synthesized by reflux method. The structural properties of the prepared NC had been characterized using PXRD, SEM, TEM, Raman, PL and XPS analysis. Further, the excellent photocatalytic properties of NC for the decomposition of reactive blue 4 compared to commercial P25 can be attributed to its excellent electrical properties and well connected arrangement derived from the structural reward of the ZrO
2
and rGO support. This results in significant electron-acceptor/transport of graphene materials that effectively decrease the photo-generated electron-hole recombination thereby enhancing the absorption of light. It opens new window to use this eco-friendly, simple and low cost method to synthesize reduced graphene-based composite materials.
ZrO
2
/rGO nanocomposite prepared
via
simple bio-mediated route exhibited excellent sunlight driven photocatalytic performance.
Green route synthesis of ZnO nanostructures with various morphologies for multifunctional applications. Display omitted
•A simple, green route has been employed to prepare various morphologies of ZnO ...NPs.•Various morphologies of NPs are dependent on the concentration of neem plant extract.•NPs showed significant activity against Klebsiella aerogenes and Staphylococcus aureus.•Bullet shaped ZnO NPs have shown significantly high antioxidant activity.•Bullet shaped NPs exhibited superior Sunlight and UV light driven photocatalytic performance.
Green synthesis of multifunctional Zinc oxide nanoparticles (NPs) with a variety of morphologies were achieved by low temperature solution combustion route employing neem (Azadirachta indica) extract as fuel. The nanoparticles were characterized by PXRD, FTIR, XPS, Raman and UV–Visible spectroscopic studies. The Morphologies were studied by SEM and TEM analysis. The NPs were subjected for photoluminescence, photocatalytic, antibacterial and antioxidant activity studies. PXRD pattern confirmed the hexagonal wurtzite structure of the product. SEM images indicated the transformation of mushroom like hexagonal disks to bullets, buds, cones, bundles and closed pine cone structured NPs with increase in the concentration of neem extract in reaction mixture. The NPs exhibited prominent green emission due to the presence of intrinsic defect centers. The as-formed bullet shaped ZnO with 4ml of neem extract was found to decolorize Methylene blue (MB) under Sunlight and UV light irradiation. The antibacterial studies indicated that ZnO NPs of concentration 500, 750 and 1000μg resulted in significant antibacterial activity on Klebsiella aerogenes and Staphylococcus aureus but not against Escherichia coli and Pseudomonas aeruginosa in agar well diffusion method. Further, ZnO NPs exhibited significant antioxidant activity against scavenging DPPH free radicals. The current investigation demonstrated green engineering method for the synthesis of multifunctional ZnO NPs with interesting morphologies using neem extract.
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•ZrTiO4:Eu3+ was synthesized by Green method using Aloevera gel as reducing agent.•The synthesized sample were characterized by different techniques.•The crystallite size varies ...inversely with optical energy band gap.•The photoluminescence analysis shows their importance in display technology.•Judd-Ofelt parameters and their derivatives are discussed in detail.
The Europium activated (1–9 mol %) Zirconium Titanate nanoparticles (NPs) have been synthesized by the green solution combustion method using Aloe Vera gel extract as a reducing agent, followed by the calcination at 720 °C for 3hrs. All the synthesized samples crystallize in a pure orthorhombic crystal structure with the space group of Pbcn. The surface and bulk morphology were analyzed. The crystallite size increases, whereas the direct energy band gap was found to decrease with an increase in dopant concentration. Further, the effect of dopant concentration on the photoluminescence properties was studied. The presence of Eu3+ ion in the trivalent state in the host lattice was confirmed by its characteristic emission at 610 nm due to 5D0→7F2 (λex = 464 nm). The CIE coordinates were found in the red region of the CIE 1931 diagram. The CCT coordinates lie in the range 6288–7125 K. The Judd-Ofelt parameters and derived quantities were analyzed. This theory confirms the high symmetry of Eu3+ ions in the host lattice. These findings imply that ZTO:Eu3+ can be employed as a nanopowder material in a red-emitting phosphor material.
In the present work, host and cerium-doped Zinc chromite nanoparticles (NPs) are synthesized by solution combustion method using Aloe Vera gel extract. The synthesized samples are characterized with ...different techniques. The Bragg reflections of ZnCr2O4:Ce (0–9 mol%) NPs confirms the formation of pure spinel cubic structure. The crystallite size, lattice strain, crystallinity, dislocation density were determined using Scherrer’s and W–H plot method. The direct energy band gap was tuned from 3 to 2.8 eV. The direct energy band gap was found to decrease with increase in the dopant concentration. The cytotoxic properties of ZnCr2O4:Ce (0–9 mol%) NPs were tested against breast cancer cell (MDA-MB-231) and compared with that of Cisplatin, a standard drug. From the MTT assay, it is confirmed that the MDA-MB-231 cells are more sensitive to doped ZnCr2O4: Ce (1–9 mol%) NPs than the host matrix as well as with the standard drug Cisplatin. Compared to other dopant concentrations, the efficiency of ZnCr2O4: Ce (9 mol%) is more than that of the cisplatin and hence this can be used as the substitute for the cisplatin.
For the first of its kind ZnAl
2
O
4
: Ag (1–11 mol
%
) nanomaterials (NMs) are synthesized using
Tulsi
leaves extract (calcination at 500
∘
C) and subjected to characterization. Structural and ...electrochemical properties are analyzed. Cubic structure is verified by the Bragg reflections. Both crystallite size and direct energy band gap was found to decrease with an increase in dopant concentration. On the surface morphology, there are numerous pores and hollows. The galvanostatic, CV, EIS spectra, Discharge profile and Cyclic life profile was performed for ZnAl
2
O
4
: Ag (1 and 11 mol
%
) NPs. The CV analysis showed only a pair of oxidation peaks and only one reduction peak. According to records, the precise discharge and charge capabilities are 242/214, 196/184, 161/151, 140/126 and 126/115 at 0.1, 0.25, 0.5, 1 and 2.5 C respectively. Additionally, at 2.5 C, the ZnAl
2
O
4
: Ag (1–11 mol%) anode exhibits the greatest cycle stability and Columbic efficiency even after 1000 cycles of cycling.
MgO-ZnO-Ga2O3 nanocomposites are synthesized by solution combustion method using Aloe Vera gel as a reducing agent to increase the efficiency of blue emission. The appearance of Bragg reflections ...corresponding to MgO, ZnO and Ga2O3 clearly indicates the formation of nanocomposites. The surface morphology consists irregular shape and sized NPs. The Energy dispersive X-ray analysis confirms the purity of the sample. The band energy gap was tuned to 3.1 eV. The Photoluminescence excitation and emission spectra was discussed and compared it with emission spectra of individual oxides as well as with other reported blue emitted nanophosphors. Further, the chromaticity coordinates and Color correlated temperature coordinates clearly confirms their warm blue emission. Further, the powder dusting method was employed to collect the latent fingerprints on the pores and non-pores surfaces. The synthesized MgO-ZnO-Ga2O3 nanocomposites exhibits well-resolved ridge patterns that can be used to identify latent finger prints with clarity. From all these results, the present synthesized MgO-ZnO-Ga2O3 nanocomposite might find an application in display technology as a blue nanophosphor material and for latent finger print detection in crime investigation.
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•Mgo-ZnO-Ga2O3 nanocomposite was synthesized by Bio mediated route using Aloe Vera extract.•Structural, Phase diagram, Optical and Latent fingerprint analysis was performed.•The might be a potential candidate for display technology, cool blue light emitting diodes, florescence boards and in forensic science.
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•Bio-mediated route has been employed to prepare multifunctional CeO2 NPs.•CeO2 nanophosphor could be a promising candidate for cool blue LEDs.•CeO2 NPs showed superior photo ...catalytic activity under UVA and Sunlight.•NPs exhibit significant antibacterial activity against Escherichia coli and Staphylococcus aureus.
Spherical shaped cerium dioxide (CeO2) nanoparticles (NPs) were synthesized via bio mediated route using Leucas aspera (LA) leaf extract. The NPs were characterized by PXRD, SEM, UV–Visible techniques. Photoluminescence (PL), photocatalysis and antibacterial properties of NPs were studied. PXRD patterns and Rietveld analysis confirm cubic fluorite structure with space group Fm-3m. SEM results evident that morphology of the NPs was greatly influenced by the concentration of LA leaf extract in the reaction mixture. The band gap energy of the NPs was found to be in the range of 2.98–3.4eV. The photocatalytic activity of NPs was evaluated by decolorization of Rhodamine-B (RhB) under UVA and Sun light irradiation. CeO2 NPs show intense blue emission with CIE coordinates (0.14, 0.22) and average color coordinated temperature value ∼148,953K. Therefore the present NPs quite useful for cool LEDs. The superior photocatalytic activity was observed for CeO2 NPs with 20ml LA under both UVA and Sunlight irradiation. The enhanced photocatalytic activity and photoluminescent properties were attributed to defect induced band gap engineered CeO2 NPs. Further, CeO2 with 20ml LA exhibit significant antibacterial activity against Escherichia coli (EC) and Staphylococcus aureus (SA). These findings show great promise of CeO2 NPs as multifunctional material for various applications.
In the present communication, for the first time Ba–Fe–Ni oxide nanocomposite (BFNONC) was synthesized by using solution combustion method and calcined at 500oC. The synthesized sample was ...characterized using the techniques such as powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Fourier transmission infrared spectroscopy (FTIR) and UV–Visible spectrophotometer to determine phase purity, functional group, surface morphology, structural analysis and energy band gap. The presence of diffraction peaks corresponding to BaO, Fe2O3 and NiO clearly confirms the formation of BFNONC. The average crystallite size was found to be 30 nm. The direct energy band gap determined by using Wood and Tauc's relation was found to be 2.1 eV. Further, the X-ray/gamma ray shielding properties of BFNONC in the energy range 0.081–1.332 MeV using NaI (Tl) detector and multi channel analyser (MCA) were measured. The measured shielding parameters are compared with the theory. Above 356 keV energy of X-ray/gamma ray, the measured shielding parameters agrees well with the theory, whereas slight deviation is observed below 356 keV. This deviation is mainly due to the influence of atomic/crystallite size of the BFNONC. This BFNONC finds an application as a shielding material in radiation shielding.
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•For the first time Barium–Iron–Nickel Oxide nanocomposite was synthesized by using solution combustion method.•The synthesized samples were characterized by using different techniques.•The X-ray/radiation shielding properties and parameters are discussed in detail.
Herein, we report the synthesis of SnO2 nanoparticles by combustion method using two reducing agents. One with urea as a fuel (SnO2U) and another one with Azadirachtaindica leaves extract as a ...reducing agent (SnO2N) and calcined at 500oC for 3 hrs. The synthesized samples are characterized using different techniques. The Bragg reflections confirms the formation of pure tetragonal SnO2 NPs. The surface morphological analysis clearly indicates the formation of irregular shaped agglomerated NPs. The agglomeration and particle size was found to be more in SnO2U NPs. The estimated direct energy bandgap using Tauc's relation was found to be 3.75 and 3.37 eV for SnO2U and SnO2N respectively. Further, Photoluminescence excitation, emission, CIE and CCT analysis was performed. Thus, the present sample might be used as a nanophosphor material in Cool and Warm blue light emitting diodes. The cytotoxic properties against HeLa and MCF7 cells and compared the percentage of viability and cell death with standard chemotherapy drug Cisplatin. Theoretically, X-ray/gamma ray absorption properties such as mass attenuation coefficient (MAC) SnO2U and SnO2N NPs were evaluated which might finds an application in nuclear radiation dosimetry.
•Tin oxide nanoparticles are synthesized by chemical and green approach.•Photoluminescence, cytotoxic and X-ray/Gamma ray interaction parameters are discussed.•Facile, economical, ecofriendly and efficient method is used for multiple applications.
For the first time, chromium substituted calcium hexaferrite (CaCr
x
Fe
12
-
x
O
19
(x = 0,2,4,6 and 8)) nanoparticles (NPs) are synthesized by
Musaparadisiaca
(banana) peel extract mediated solution ...combustion method followed by calcination at 500
o
C. The Bragg reflections confirms the formation of M-type hexaferrite with P6
3
/
m
m
c
space group. No other impurity peaks are observed, except the variation in intensity and width of the peaks. The surface morphology consists irregular shaped NPs. Agglomeration of NPs was found to be maximum at CaCr
x
Fe
12
-
x
O
19
(x = 8). The optical energy band gap was calculated using Wood and Tauc’s relation which found to be in the range 3.31 to 2.92 eV. The energy band gap decreases whereas the crystallite size increases with increase in chromium substitution. The radiation shielding parameter- mass attenuation coefficient is measured and its derivatives such as mean free path, half value layer, effective atomic number, electron density, energy absorbing building factor variation at different energy region are discussed in detail along with neutron shielding and Bremsstrahlung radiation parameters with respect to chromium concentration in calcium hexaferrite NPs. These parameters plays an important role in radiation dosimetry.
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