The present study is demonstrating the deposition of solution based nanostructured silver top electrode for inverted organic solar cells. The deposition of silver nanoparticles through hybrid ...electrohydrodynamic atomization (Hybrid-EHDA) is discussed in detail. The film thicknesses were varied with respect to spray times. The interface between the metal electrode and organic film was investigated using a focused ion beam analyzer. The sheet resistance of nanostructured silver film was reduced by increasing the film thickness. The lowest sheet resistance of silver film is ~0.07Ω/sq with a film thickness of 2.6µm. The power conversion efficiency of fabricated devices was found to be influenced by the sheet resistance of silver film. The maximum power conversion efficiency (~2.44%) was observed at 0.07Ω/sq. Our results demonstrate that the Hybrid-EHDA will play a promising role in the fabrication of inverted organic solar cells using a solution based top electrode.
•Hybrid-electrohydrodynamic atomization of silver top electrode.•Film uniformity and sheet resistances are varied with respect to spray time.•The lowest sheet resistance of 0.07Ω/sq is observed at the spray time of 8min.•The power conversion efficiency of fabricated solar cell is found to be 2.44%.
Selective detection of metal ion is a major research interest in the field of sensors development for environmental safety. Herein, a facile, cost-effective and eco-friendly method is developed to ...synthesis carbon dots (CDs) from plant material (Plectranthus amboinicus) without any harmful chemicals. As-synthesized CDs exhibited bright blue emission under an excitation wavelength of 390 nm. The Fourier-transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analysis confirmed the presence of functional groups with respective binding energies (hydroxyl and carboxyl groups) on the surface of CDs. The interaction between CDs and metal ions is examined by the influence of fluorescent intensity changes with respect to the quenching effect of CDs. When compared to the other metal ions, silver ion (Ag+) had an excellent fluorescent quenching of CDs. The fluorescence intensity of CD exhibited a good linear correlation efficiency for the detection of Ag+ ion from 0-30 nM (R2 = 0.9905) with a detection limit of 10 nM. In addition, an excellent color change is observed (colorimetric analysis and visible eye observation) for silver ion reduction (from Ag+ into Ag0) compared with other metal ions (no specific color changes). This method is simple, sensitive and selective for colorimetric and fluorescence analysis of Ag+ in a water sample.
Silver nanowires (AgNWs) films were coated conformally with aluminum oxide (Al
2
O
3
) through atomic layer deposition (ALD) at very low temperature. The AgNWs films were first fabricated through ...spin coating on polyamide substrates. Later on Al
2
O
3
coatings were deposited on the spin coated AgNWs films by ALD at a very low deposition temperature of 50 °C using trimethylaluminum and distilled water. The optimized ALD cycle involves a very short H
2
O purging step of only 10 s, which not only removes the residual H
2
O vapors effectively but also enhances the efficeny of the process by reducing the total time required for completion of Al
2
O
3
deposition. The surface morphology was observed through field-emission scanning electron microscopy and film crystallinity using X-ray diffractometer, respectively. The observed results revealed conformal and amorphous nature of Al
2
O
3
coatings on AgNWs films. The chemical composition and films purity were analyzed by X-ray photoelectron spectroscopy. It has been verified by the results that the ALD technique is well capable of depositing uniform Al
2
O
3
coatings on AgNWs films at very low temperature. The deposited coatings are expected to be of very much interest in flexible electronic applications in near future.
An effective method for the fabrication of thin film of single wall carbon nanotubes (SWCNT) using the electro-hydrodynamic atomization (EHDA) deposition technique was demonstrated. In this study, ...the SWCNT aqueous based dispersion ink was subjected to electrostatic atomization by using an EHDA deposition system. The ink flow visualization under the influence of electric field was performed and the operating EHDA parametric envelope of the ink was explored. Then the deposition of SWCNT through the EHDA process was carried out onto a metallic substrate at a fixed flow rate and corresponding applied voltage thereby achieving thickness ranging from ∼70 to 130 nm by making multiple deposition passes. The microscopic inspection of the film was performed and thin film quality was examined by scanning electron microscope analysis. Finally, electrical behavior of the SWCNT film onto a metallic substrate through temperature dependent current-voltage measurements was investigated. The SWCNT film deposited onto the metallic substrate showed electrical conductivity of ∼2.98 S/cm.
We report an indium-tin-oxide (ITO) coated silicon (Si) pillar arrays heterojunction device for providing high performing photoresponse. The photolithography is used to fabricate the periodic ...patterns of Si pillar arrays with two different widths/periods: 2 μm/5 μm
and 2 μm/7 μm at constant depth (1.1 μm). A transparent and antireflective ITO coated Si pillar arrays are achieved at a room temperature and then subjected to rapid thermal process at 300 °C for 10 min. The reflectance of 2/5 pillar patterns revealed the
lower value of 14.4% than that of 2/7 pillar patterns (reflectance of 25.8%). The photoresponse of fabricated heterojunction device is enhanced in response with surficial length. The highest photoresponse ratios of 1656% and 1556% are observed for prepared devices at a wavelength of 900 nm.
These results confirmed that the improved photoresponse is observed by surficial length enhancement. Therefore, the fabricated ITO coated Si heterojunction play an important role in photovoltaic devices.
We investigated different molar concentrations of cobalt precursor intercalated reduced graphene oxide (rGO) as possible electrode materials for supercapacitors. Cobalt oxide (Co
3
O
4
) nanocubes ...intercalated reduced graphene oxides (rGO) were synthesized
via
a facile hydrothermal method. It has been found that the Co
3
O
4
particles with a cubical shape are decorated on rGO matrix with an average size of ∼45 nm. The structural crystallinity of rGO-Co
3
O
4
composites was examined by X-ray diffraction (XRD). Raman spectroscopy confirmed the successful reduction of GO to rGO and effective interaction between Co
3
O
4
and the rGO matrix. The electrochemical performances of rGO-Co
3
O
4
electrodes were examined using cyclic voltammetry and charge-discharge techniques. The maximum specific capacitance (278 F g
−1
) is observed at current density of 200 mA g
−1
in the C2 electrode resulting from effective ion transfer and less particle aggregation of Co
3
O
4
on the rGO matrix than in the other electrodes. C2 exhibits good rate capability and excellent long-term cyclic stability of 91.6% for 2000 cycles. The enhanced electrochemical performance may result from uniform intercalation of cobalt oxide over the rGO. These results suggest that the Co
3
O
4
intercalated rGO matrix could play a role in improved energy storage capability.
We investigated different molar concentrations of cobalt precursor intercalated reduced graphene oxide (rGO) as possible electrode materials for supercapacitors.
A number of materials are now available to alleviate the ever-growing bone disruption. However, these are inadequate and inappropriate for addressing issues associated natural process of aging and ...degeneration of bone due to diseases. This study advances the existing material and offers more privileged and synergistically active remedy for these conditions. Here, they are three different nano-composites prepared such as nano-TiO2 with chitosan (TC), nano-TiO2 with chondroitin 4-sulfate (TG), and nano-TiO2 with chitosan and chondroitin 4-sulfate (TCG), whereas nano-TiO2 act as a control. The prepared nanocomposite was studied for determining its bactericidal and fungicidal activity by using disk diffusion method. In addition, the osteoinductive, free radical forming, and scavenging abilities of the nanocomposite treated MG-63 cell lines were analyzed using gene expression and biochemical analysis respectively. The augmented fungicidal (~16mm) activities of TCG against bone-infecting pathogens can be effectively used in bone transplantation application. The expression of osteoblast-inducing genes in MG-63 cell line and their up-regulation in nanocomposite treatment, especially in TCG, made this material more desirable. The formation of free radicals such as thiobarbituric acid reactive substance and nitric oxide gradually reduced with the treatment of nanocomposites than control and nano-TiO2. Contrarily, it was found that MG-63 along with nanocomposites statistically increases the production of ALP, antioxidant enzymes (super oxide mutase) and total antioxidant activity (ferric reducing antioxidant power) in several folds compare with the control and nano-TiO2. All the results with statistical scale suggest TCG as an effectual and affordable biomaterial in bone regeneration therapy among the prepared samples.
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•The augmented fungicidal (~16mm) activity against bone-infecting pathogens•The significant reduction in free radicals formation with TCG treated MG-63•TCG up-regulates the production of ALP, SOD and FRAP in MG-63.•Offers more privileged and synergistically active remedy for bone degeneration
