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A novel CaFe2O4/CQDs 90% degradation of carcinogenic Congo red dye observed. Modification of CaFe2O4 with CQDs narrowed its bandgap.

In this work, graphene was produced by liquid-phase exfoliation of graphite in different organic solvents with addition of picric acid. The graphene was easily produced by one step ultra-sonication of graphite powder in the organic solvents. The addition of picric acid has increased the graphene production yield in most of the solvents tested in this work. Picric acid serves as a “molecular wedge” to intercalate into the edge of graphite, which plays a key role during sonication and significantly improves the production yield of graphene. The products were analyzed by microscopic techniques, including atomic force microscopy (AFM) and scanning electron microscope (SEM). The AFM images indicate that the exfoliation efficiency and amount of graphene increased by addition of picric acid in organic solvents. Moreover, the AFM images also indicate presence of bilayer graphene. SEM analysis also shows that the addition of picric acid into the organic solvent favors the exfoliation process. The produced graphene was also analyzed by XRD, FTIR, Raman and UV-visible spectroscopy. The XRD results illustrate that exfoliation was best achieved in N-methyl-2-pyrrolidone (NMP) as a solvent. FTIR and Raman results indicate that addition of picric acid has slightly defected the produced graphene surface. The amount of graphene concentration was calculated by using Beer Lambert law, and it was observed that the graphene production yield was increased by using picric acid in most of the solvents. The maximum amount of graphene concentration (0.159 mg/ml) was achieved by adding 30 mg of picric acid in NMP.

The present work reports the in-situ ion beam induced luminescence measurements using 2 MeV proton excitation of LiF single crystal with the aim of obtaining a further insight on F-type centers kinetics and its correlation with the self-trapped exciton (STE). It is found that the STE luminescence intensity decreases from the beginning of irradiation. While the dose-dependent evolution of F3+ and F2 centers reveals three kinetic stages: (i) linear increase from the beginning of irradiation up to 10.1 MGy, followed by (ii) monotonic decrease to 18.1 MGy, and (iii) steady state from 18.1 to 26.2 MGy where the luminescence intensity remains constant. The STE luminescence completely extinguished at high dose; 18.1 MGy in our case. Whereas, the F3+ and F2 luminescence persist and remain constant above 18.1 MGy. The latter behavior revealed in the present study can be useful for LiF application in radiation dosimetry and an imaging detector.

The rare earth (Yb3+) substituted W-type hexagonal ferrites with composition CaPb2-xYbxFe16O27 (x = 0.0, 0.5, 1.0, 1.5, 2.0) were synthesized by a facile and cost-effective sol-gel auto combustion method with post heat treatment. The synthesized hexagonal ferrites were characterized by a variety of analytical techniques, and an impedance analyzer was used to investigate the effects of Ytterbium on structural, magnetic, spectral and dielectric properties. The relationship between their impedance, structure and dielectric properties was investigated. The X-ray diffraction patterns verify the presence of single-phase W-type hexagonal ferrites. Physical properties such as Dbulk (bulk density), Dxrd (X-ray density), and P (porosity) of the CaPb2-xYbxFe16O27 W-type hexagonal ferrites were calculated. The bulk density of all the samples was decreased, and X-ray intensity was increased with the Ytterbium replacement in the W-type hexaferrite. By adding Yb3+ ions, the lattice parameters, cell volume and X-ray density were reduced due to the substitution of ytterbium with smaller ionic radii compared to the lead ion with large ionic radii. The AC-conductivity was increased from (1.523 × 10−5 to 6.699 × 10−5) Ωcm−1. The dielectric constant and tangent loss was found to decrease substantially. The magnetic properties were found to enhance by the substitution of Yb3+. The low coercivity value of Yb3+ substituted W-type hexagonal ferrites are suitable for magnetic recording media operated at a high-frequency regime. The enhancement of electrical, dielectric and magnetic characteristics suggests these materials as promising for multi-layer chip inductors (MLCIs) circuit applications.

Surfactant -treated tin oxide (SnO

Herein, we present pure nickel oxide nanoparticles (NiO NPs) and Sr doped NiO NPs SrxNi1−xO (x = 0.0, 0.01, 0.02, 0.03, 0.04) which are synthesized via hydrothermal approach. As-synthesized samples are analyzed through structural characterization techniques like x-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The single cubic phase is obtained for NiO NPs and the samples with low Sr dopant contents (1% to 2%); however, samples with high Sr dopant contents (3% to 4%) have a secondary phase (SrO phase). The particle size of Sr doped NiO NPs ranges from 50–100 nm, and the particles lose their uniformity as dopant concentration is increases. Electrical and dielectric characteristics of as-synthesized samples are studied, and the effect of Sr dopant contents is discussed. Electrochemical studies reveal that the selected samples exhibit remarkable catalytic activity toward glucose sensing owing to their specific structural and morphological characteristics.

Electrical conductivity and optical transmittance of Nickel Nanowires (Ni-NWs) networks was reported in this work. The Ni-NWs was irradiated with 3.5 MeV, 3.8 MeV and 4.11 MeV proton (H+) ions at room temperature. The electrical conductivity of Ni-NWs networks was observed to increase with the increase in beam energies of H+ ions. With the increase in ions beam energies, electrical conductivity increases and this may be attributed to a reduction in wire-wire point contact resistance due to the irradiation-induced welding of NWs. Welding is probably initiated due to H+ ions-irradiation induced heating effect that also improved the crystalline quality of nanowires (NWs). After ion beam irradiation, localize heat is generated in nanowires due to ionization which was also verified by SRIM simulation. Optical transmittance is increased with increase in energy of H+ ions. The Ni-NWs networks subjected to an ion beam irradiation to observe corresponding changes in electrical conductivity and optical transparencies are promising for various nano-technological applications as highly transparent and conducting electrodes.

In this paper, formation of defects/defect clusters in nickel nanowires (Ni-NWs) due to interaction of a 60 kilo-electron-volt (keV) beam of proton (H[Formula: see text] ions is studied. Ni-NWs are exposed to various fluencies of H[Formula: see text] ions ranging between [Formula: see text] and [Formula: see text][Formula: see text]ions/cm2. The analysis of pristine and H[Formula: see text] ion-irradiated Ni-NWs samples is mainly done using transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. Stopping range of ions in matter (SRIM) simulation software is employed to verify the production of defect clusters in Ni-NWs theoretically. Furthermore, insight of creation of defects in Ni-NWs due to interaction of low energy H[Formula: see text] ions in keV range is made using the theory of collision cascade effect. The study of defect clusters induced in Ni-NWs under H[Formula: see text] ions beam irradiation is essential for application of Ni-NW-based nanodevices in harsh environment containing plenty of H[Formula: see text] ions such as for use in spacecraft equipped for space missions.

Irradiation induced damage study of Cu-NWs by 5 MeV H+ and C+ ions on the structural and morphological properties were examined in detail. The XRD spectra and HRTEM analyses of the formulated Cu-NWs give good crystallinity with the best orientation peak at (111) directions. The effect of H+ and C+ ion irradiation induce a decrease of the (111) peak intensity due to the structural defect formation, as observed by HRTEM. It also leads to the formation of Cu2O phase and an increase in the Cu-NWs diameter, signifying NWs swelling. We observed an increase in the Cu2O phase intensity at a high fluence of 5 MeV H+ irradiation. This phase decreased when the sample was irradiated with 5 MeV C+ ion. Since there was no shifting of the observed diffraction peak at (111) towards a lower angle, we can conclude that the NWs swelling is not due to the lattice parameter dilation but probably to the Cu2O phase formation. Therefore we can conclude that H+ and C+ ion irradiation on Cu-NWs leads to the Cu/CuO composites formation, which may find applications chiefly in nano-devices.

Influence of 30 kilo-electron-volt (keV) Argon (Ar+) ions on optical and electrical properties of nickel nanowires (Ni-NWs) meshes is being reported. Ni-NWs are being exposed to 30 keV Argon (Ar+) ions at various beam fluencies. These fluencies of Ar+ ions are 7 × 1014 ions cm−2, 3 × 1015 ions cm−2 and 3 × 1016 ions cm−2. After irradiation, Ni-NWs meshes were analyzed through transmission electron microscopy technique (TEM). The structural analysis has been done through X-ray diffraction technique. It is found from TEM results that atoms are sputtered out from surfaces of Ni-NWs due to collision cascade effect persistently and lead to reduce the diameters or thicknesses of Ni-NWs. X-ray diffraction results reveal that crystalline quality is reduced under Ar+ ions irradiation which may be due to defects induced in Ni-NWs as a result of collision cascade effect. The Ni-NWs meshes are characterized optically and electrically through UV–VIS spectroscopy and four probe techniques. The optical transparencies of Ni-NWs meshes are increasing with increase in beam fluence of Ar+ ions. The electrical conductivity of the mesh is decreased continuously with increment in beam fluence of Ar+ ions which might be due to production of defects in Ni-NWs. The tuning of optical transparency and electrical conductivity of Ni-NWs meshes is required for their application as successful transparent electrodes in optoelectronic nanodevices.

MeV carbon ion irradiation-induced changes in the electrical conductivity of Silver nanowire (Ag-NW) networks is demonstrated systematically at different C + ion fluences ranging from 1 × 10 12 to 1 × 10 16 ions/cm 2 at room temperature. At low C + ion fluences, the electrical conductivity of Ag-NWs decreases and subsequently increases with increase fluence. Finally, at high C + ion fluences, conductivity again decreases. The variation in the electrical conductivity of Ag NW network is discussed after analysis using scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The observed increase in electrical conductivity is thought to be due to ion induced coalescence of Ag-NWs at contact position, which causes reduction of wire–wire contact resistance, while the decrease in electrical conductivity may be due to defect production by C + ions into Ag-NWs. Ion beam technology is therefore a very promising technology that is capable of fabricating highly conductive Ag-NW networks for transparent electrodes. Moreover, a method for thinning, slicing and cutting of Ag-NWs using ion beam technology is also reported.

Interconnections between Ag- NWs Build by Argon Ions Beam Irradiation Interconnection between Ag-NWs is essential for the integration and assembly of NWs networks to enable optoelectronics and nanoelectronics applications. In this report, joining of Ag-NWs through argon ion beam irradiation technology is demonstrated. A range of experimental traits of constructing X-, and II-shapes molecular junctions between Ag nanowires and the utilization of the argon ion beam irradiation induced nanowelding technique to form functional metal NWs networks is conferred. Scanning electron microscopy, X-ray diffraction and transmission electron microscopy results revealed that Ag-NWs are effectively connected to each other on intersecting positions. These networks are optically transparent and crystal structure remained un-damaged. Besides, technical hindrances facing the ion irradiation induced nanowelding technology are also discussed. A perspective is given for using argon ion irradiation induced welding technique for the construction of random networks of well-connected nanowires.

Measurement of differential elastic cross section of protons from aluminum was taken at 165° degree in the 2.4–4.8 MeV energy range. The results and measured energy resonances were compared with reported measurements. These data will improve the reliability of backscattering analysis of Al with protons in this energy region.

In the present work, Zinc Sulphide (ZnS) thin films deposited by resistive heating technique on BK-7 glass substrate. Optical and structural characterizations of ZnS films have been carried out along with the post-deposition annealing at different temperatures. The thickness of the film is monitored by quartz crystal monitor and found to be 500[Formula: see text]nm. Fourier transform infrared (FTIR) spectroscopy provides the qualitative analysis of ZnS film before and after annealing at different temperatures. The optical investigation shows that the as-deposited and annealed ZnS film display the high optical transmittance of (64–68%) in the visible/near infrared region. The optical energy gaps of present as-deposited and annealed ZnS film vary in the range of 3.32–3.18[Formula: see text]eV with the change in annealing temperature.

Copper nanowires (Cu-NWs) are leading contenders to replace indium tin oxides (ITOs) based traditional transparent conducting electrodes from the market due to their high mechanical flexibility and low-cost. In this work, Kilo-electron-volt (KeV) hydrogen (H+) ions beam irradiation-induced reduction in diameters of Cu-NWs is examined through transmission electron microscope (TEM) and scanning electron microscope (SEM). The reduction in diameters of Cu-NWs is found to occur via H+ ions beam irradiation-induced collision cascade of atomic displacements mechanism lead to continual reorganizing Cu atoms in individual Cu-NWs lattices. Formation of defect clusters or loss of crystal structure is not found in x-ray diffraction (XRD) patterns due to H+ ions beam irradiation. These experimental findings may potentially be applied to enhance spaces between NWs in complex Cu-NWs meshes for application as transparent conducting electrodes. Moreover, this study has also significance in exploring the possibility for application of Cu-NWs meshes based optoelectronic devices in harsh environment containing plenty of H+ ions such as for use in spacecrafts for upper space missions.

In order to replace conventional transparent conducting electrodes, metal nanowires (MNWs) networks have long been act as promising contenders due to their high mechanical flexibility. However, nanowire-nanowire contact resistance is main technical obstruction in terms of improvement in their performance. To reduce nanowire-nanowire contact resistance, welding of nanowires (NWs) is essential. In this work, MeV proton and argon ions beam irradiation induced nanoscale welding technique to fabricate X-, Y-, II- and T-shaped molecular junctions between nickel nanowires (Ni-NWs) is presented. Ni-NWs are irradiated by 2.75 MeV proton ions and 3.5 MeV argon ions at doses 1x1016ions/cm2 and 5x1015 respectively while temperature is kept constant. Transmission electron microscopy (TEM), scanning electron microscopy (SEM) and x-ray diffraction (XRD) results reveal that Ni-NWs are welded without losing stability in crystal structures of NWs. Afterward, a two-dimensional large scale random network of Ni-NWs is fabricated by 3 MeV proton ions beam irradiation induced nanoscale welding of Ni-NWs at crossing positions. Proton ion beam induced large scale network fabrication is confirmed by TEM and SEM techniques. Moreover, these networks are characterized optically using UV-VIS spectroscopy. It is observed that at a beam fluence of 5x1015 ions/cm2, perfect molecular junctions between Ni-NWs in X-, II-, and V-shapes are achieved and a large scale welded network of Ni-NWs is obtained without distorting the morphology of NWs. Moreover, structure of Ni-NWs remains stable under 3MeV proton ions beam irradiation and networks are found to be optically transparent. The results exhibit that fabrication of Ni-NWs network precede through three steps: i- High energy ions beam irradiation induced heat spikes lead to locally heat and fuse Ni-NWs, ii- Formation of molecular junctions on small scale, iii- Formation of large scale network Ions beam irradiation induced welding of Ni-NWs can improve performance of NWs networks by reducing contact resistance between NWs for application as transparent conducting electrodes. These high quality welded MNWs networks may potentially be applied as transparent conducting electrodes in optoelectronic devices.

The effect of copper ions (Cu+) of various fluencies on optical and electrical properties of silver nanowires (Ag-NWs) thin films is investigated. It is found that electrical conductivity and optical transmittance rises with increase in fluencies of copper ions. At 3x1015 ions/cm2, optical transmittance of Ag-NWs thin films increased upto 80 % in the visible (Vis) region and 55% in ultraviolet (UV) region in comparison with pristine Ag-NWs thin films. At the same beam fluence of Cu+ ions, electrical conductivity is raised thrice to that of pristine value. The increase in optical transmittance is attributed to Cu+ ion beam irradiation-induced localize heating effect cause melting and slicing of Ag-NWs, whereas Cu+ ion beam induced fusion of Ag-NWs at contact points is the main reason to enhance electrical conductivity. This study offers a technical base for designing of transparent conducting electrodes (TCEs) based on Ag-NWs thin films for multiple photovoltaic applications. Besides, this investigation is also helpful for application of photovoltaic devices based on MNWs thin films in radiations containing environment such as upper space.

Metal nanowires (MNWs) are proven to be excellent innovative conducting materials for next generation of nanodevices either in form of transparent electrodes for solar cells or for interconnecting conducting nanowires to incorporate multiple nanodevices. To exploit exceptional properties of MNWs networks in future nanodevices, effective joining between various types of MNWs is critical. This study is based on joining of copper nanowires (Cu-NWs) and nickel nanowires (Ni-NWs) through argon (Ar+) ions beam irradiation. Scanning electron microscopy (SEM), x-ray diffraction (XRD) and transmission electron microscopy (TEM) results exposed that Ag-NWs are effectively connected to each other on intersecting positions and crystal structure also remained un-damaged. In addition, the results exhibit that Ar+ ions beam irradiation induced sputtering of atoms from NWs lattices lead to produce point defects and accumulation of these point defects on crossing sharp angle contact areas, eventually lead to connect these NWs. A basic perception is the exploitation of Ar+ ions beam irradiation induced nanowelding technique for construction of complex and random networks of well-connected multiple MNWs for application in future nanodevices or optoelectronic devices.

This report is based on study of defect clusters or amorphous matrices induced in nickel nanowires (Ni-NWs) due to interaction of a beam of ~ 60 KeV hydrogen (H+) ions. Ni-NWs are exposed to various fluencies of hydrogen (H+) ions ranging between ~ 1014 ions/cm2 to 1017 ions/cm2. The analysis of pristine and hydrogen (H+) ions irradiated Ni-NWs samples has been mainly done using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction (XRD) techniques. SRIM (stopping range of ions in matter) simulation is performed to corroborate the production of defect clusters/amorphous matrices in Ni-NWs theoretically. Moreover, basic insight of defect creation in Ni-NWs due to interaction of low energy in kilo-electron-volt (KeV) range hydrogen (H+) ions has been built using collision cascade theory. The purpose of this analysis is to explore the possibility of application of Ni-NWs based future nanodevices in environment containing plenty of hydrogen (H+) ions such as for use in spacecrafts employed for upper space missions.

A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H+) ion beam irradiation. Ag-NWs are irradiated under H+ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H+ ion beam-induced welding of Ag-NWs at intersecting positions. H+ ion beam induced welding is confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, the structure of Ag NWs remains stable under H+ ion beam, and networks are optically transparent. Morphology also remains stable under H+ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H+ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps: ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices.

In this paper, effect of oxygen (O[Formula: see text]) ion irradiation on the properties of polycrystalline cubic structure CdTe thin films has been investigated. CdTe thin films were irradiated with O[Formula: see text] ions of energy 80[Formula: see text]keV at different fluence ranging from [Formula: see text] to [Formula: see text] [Formula: see text]ion/cm2 at room temperature. At [Formula: see text] [Formula: see text]ion/cm2 O[Formula: see text] ions fluence, the CdTe structure was maintained while XRD peaks of cubic phase were shifted toward lower angles. At [Formula: see text] [Formula: see text]ion/cm2 O[Formula: see text] ions fluence, cubic structure of CdTe thin films was transformed into hexagonal structure. In addition, electrical resistivity and optical bandgap were decreased with increasing O[Formula: see text] ion beam irradiation.

A random two-dimensional nano-network of silver nanowires (Ag-NWs) was fabricated by MeV Hydrogen (H+) ion beam irradiation. Ag-NWs were irradiated under H+ ion beam at different fluences at room temperature. Ag-NWs network was fabricated by H+ ion beam induced coalescence of Ag-NWs at the crossing and the parallel positions. H+ ion beam induced coalescence was confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, structure of Ag NWs remains stable under H+ ion beam. Threshold dose for the stability of Ag NWs structure under H+ ion beam irradiation was 5x1015 protons/cm2 at room temperature, confirmed by TEM, and XRD. Morphology also remains stable under H+ ion beam irradiation. No slicing, cutting of Ag-NWs were observed under MeV H+ ion beam irradiation. This observation is useful for using Ag-NWs based devices in upper space where protons are abandon in MeV to GeV energy ranges. The results exhibit that the formation of Ag-NWs network proceeds through three steps: ion beam induced local heating, formation of simple junctions, and the formation of large scale network. This high quality network will also be useful as a transparent electrode for optoelectronics devices.

Here, we demonstrate a MeV proton beam irradiation induced nanowelding technique to fabricate X-, Y-, T and II-shapes molecular junctions between Ag nanowires, both suspended and deposited on substrates. High-resolution transmission electron microscopy, X-ray diffraction and Scanning electron microscopy revealed that the nanoweldings are nearly perfect, with the same crystal orientation. We further discuss various experimental aspects of this method which may potentially be used for developing complicated networks of joined nanowires. The high quality of the welding is attributed to the nanoscale sample dimensions, oriented-attachment mechanisms and mechanically assisted fast surface-atom diffusion.