Energy Dispersive X-ray Spectroscopy Studies Research Articles

Experimental studies of TiO2 nanoparticles synthesized by sol-gel and solvothermal routes for DSSCs application

This paper presents the synthesis and characterization of TiO2 nanoparticles prepared by the sol–gel (SG) and solvothermal (ST) methods. The crystallinity and phase identification examined by the X-ray diffraction (XRD) evidenced the pure-anatase TiO2 nanocrystals without any impurities. The scanning electron microscopy (SEM) analysis showed the preparation of spherical-shape TiO2 nanoparticles while energy-dispersive X-ray spectroscopy (EDS) study endorsed the elemental compositions of Ti and O. Transmission electron microscopy (TEM) investigation evidenced the mesoporous microspheres of TiO2 nanoparticles with their average size 119 nm. By UV–vis spectroscopy study, the optical band gaps were estimated to be 2.9 and 3.2 eV corresponding to the samples SG and ST. Furthermore, both SG and ST samples were employed as the photoanode materials for the dye-sensitized solar cells (DSSCs) however, ST based DSSC endorsed the enhanced photovoltaic performance.

Effect of Fe addition and moist environment on the high temperature oxidation behavior of Mo76-xSi14B10Fex (x = 0, 0.5, 1 at.%) composites

The effect of Fe addition and the moist environment on the high temperature isothermal oxidation behaviors of multiphase Mo76-xSi14B10Fex (x = 0, 0.5, 1 at.%) composites in the range of 1000–1300 °C have been investigated. The microstructure of all the composites with α–Mo solid solution (SS) and eutectic mixture of Mo3Si + Mo5SiB2 phases, has been refined upon Fe addition, which improves the oxidation resistance and reduces the mass loss up to 55% in dry air and 31% in moist air for 24 h exposure. Whereas, the oxidation resistance in moist air improves due to the formation of a protective Fe-rich glassy borosilicate scale, which reduces the vaporization of MoO3 by forming Fe2(MoO4)3. The cross-sectional area of the residual alloy for x = 1 were estimated to be 97% in dry air and 85% in moist air that of unoxidized coupons. The bulk hardness of the as-cast composite is 1031 Hv for x = 1, which reduced only by 6.7% (962 Hv) upon oxidation at 1300 °C in both dry and moist air, showing superior stability of the silicide matrix composites for high temperature application. X-ray diffraction, scanning electron microscopy and energy dispersive x-ray spectroscopy studies were performed to identify the various products of oxidation and to explore the mechanism of protection.

Environmentally friendly hydrometallurgical recovery of tin and lead from waste printed circuit boards: Thermodynamic and kinetics studies

The aim of this research was to develop an environmentally friendly flowsheet to recover Sn and Pb, which are two well-known hazardous elements, from waste printed circuit boards (PCBs), resulting in solving an environmental issue besides reproducing high-value metals. In the leaching process, the highest Sn and Pb recoveries of 88% and 99% were achieved by using 2 M hydrochloric acid (HCl) at an agitation rate of 500 RPM at 75 °C. Thermodynamic evaluations were employed successfully to confirm the leaching results. The kinetics studies indicated that the reaction mechanism shifted from a mixed control model (surface reaction control and diffusion through product layer) to the diffusion control, by increasing the agitation rate. The temperature and acid concentration controlled the dissolution by the diffusion mechanism. Production of an ash layer on the particle surface suppressed Sn and Pb dissolution as a result of enhancing both the temperature and acid concentration. The results of the kinetics modeling have been validated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) studies. The activation energies for Sn and Pb were found to be 39.49 and 50.60 kJ/mol, respectively. The Fourier-transform infrared spectroscopy (FTIR) indicated the presence of alkyne and alkyl halides, as well as carboxylic and aromatic components, in the pregnant leach solution. The metallic SnPb product was obtained by using Al-based heat sink scrap separated from the same PCBs via the cementation method. The SEM and X-ray mapping studies were carried out to characterize this product. The selectivity of the cementation method for Sn and Pb was confirmed by the above-mentioned methods.

Structure and Deformation Behavior of Ti-SiC Composites Made by Mechanical Alloying and Spark Plasma Sintering.

Combining high energy ball milling and spark plasma sintering is one of the most promising technologies in materials science. The mechanical alloying process enables the production of nanostructured composite powders that can be successfully spark plasma sintered in a very short time, while preserving the nanostructure and enhancing the mechanical properties of the composite. Composites with MAX phases are among the most promising materials. In this study, Ti/SiC composite powder was produced by high energy ball milling and then consolidated by spark plasma sintering. During both processes, Ti3SiC2, TiC and Ti5Si3 phases were formed. Scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction study showed that the phase composition of the spark plasma sintered composites consists mainly of Ti3SiC2 and a mixture of TiC and Ti5Si3 phases which have a different indentation size effect. The influence of the sintering temperature on the Ti-SiC composite structure and properties is defined. The effect of the Ti3SiC2 MAX phase grain growth was found at a sintering temperature of 1400–1450 °C. The indentation size effect at the nanoscale for Ti3SiC2, TiC+Ti5Si3 and SiC-Ti phases is analyzed on the basis of the strain gradient plasticity theory and the equation constants were defined.

Facile Photochemical Syntheses of Conjoined Nanotwin Gold-Silver Particles within a Biologically-Benign Chitosan Polymer.

A simple photochemical method for making conjoined bi-metallic gold-silver (Au/Ag) nanotwins, a new breed of nanoparticles (NPs), is developed. To the best of our knowledge, the photochemical method resulted in distinct, conjoined, bimetallic nanotwins that are different from any well-established alloyed or core-shell nanostructures in the literature. The conjoined Au-Ag NPs possessed surface plasmon resonance (SPR) properties of both metals. The bimetallic nanostructures possessing distinctive optical properties of both metals were obtained using Au NPs as seeds in the first step, followed by the addition of a silver precursor as feed in the second step during a photochemical irradiation process. In the first step, small, isotropic or large, anisotropic Au NPs are generated by photoinduced reduction within a biocompatible chitosan (CS) polymer. In the second step, a silver precursor (AgNO3) is added as the feed to the AuNPs seed, followed by irradiation of the solution in the ice-bath. The entire photochemical irradiation process resulting in the formation of bimetallic Au-AgNPs did not involve any other reducing agents or stabilizing agents other than the CS polymer stabilizer. The small, conjoined Au-Ag bi-metallic NPs exhibited SPR with peak maxima centering at ~400 nm and ~550 nm, whereas the large conjoined nanoparticles exhibited SPR with peak maxima centering at ~400 nm, 550 nm, and 680 nm, characteristic of both gold and silver surface plasmons in solution. The tunability in the SPR and size of the bimetallic NPs were obtained by varying the reaction time and other reaction parameters, resulting in average sizes between 30 and 100 nm. The SPR, size, distribution, and elemental composition of the bi-metallic NPs were characterized using UV-Vis absorption, electron microscopy, and energy dispersive X-ray spectroscopy (EDS) studies.

Detoxification of dye contaminated water by Mn $$^{2+}$$ 2 + -doped ZnS nanostructures

Chemical co-precipitation route was successfully employed to synthesize polyethylene glycol-coated pure and doped $$\hbox {Zn}_{1-x}\hbox {Mn}_{x}\hbox {S}\,(0\le x \le 0.1)$$ nanoparticles. The crystallographic and morphological analyses have been done by X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The formation of cubic crystal structure and quasi-spherical morphology has been revealed by XRD and TEM, respectively. The optical analyses have been done by UV–Vis absorption spectroscopy and energy resolved photoluminescence spectroscopy. Energy dispersive X-ray spectroscopy study has been carried to analyse the elemental composition. The doping concentration dependent photo-catalytic activity was checked to analyse the photo-catalytic potential of $$\hbox {Zn}_{1-x}\hbox {Mn}_{x}\hbox {S}$$ nanoparticles under UV irradiation.

Analysis of grain growth, structural and magnetic properties of Li-Ni-Zn ferrite under the influence of sintering temperature

The effect of sintering temperature (TS) on the structural and magnetic properties of Li0.15Ni0.3Zn0.4Fe2.15O4 is investigated and discussed. The sample is synthesized by the sol-gel auto combustion method and sintered at 1373–1573 K for 5 h. Phase identification of the powder sample was performed by using the X-ray diffraction (XRD). The XRD patterns confirmed the formation of single phase cubic spinel structure. The bulk density is correlated with TS. From the energy-dispersive X-ray spectroscopy study, it is observed that the percentage of the elements in the component phases is well consistent with the nominal composition of the composites. Field Emission Scanning Electron Microscopy showed that the average grain size (D) is increased with increasing TS. The frequency (100 Hz–120 MHz) dependent complex initial permeability spectra and relative quality factor increased with sintering temperature up to 1523 K then decreased for further increase in temperature. The complex initial permeability has been explained with the help of microstructure, and the redistribution of cations in their sites.

Characterization, Antimicrobial and α-Amylase Inhibitory Activity of Silver Nanoparticles Synthesized by using Mushroom Extract of Lentinus tuber-regium

The present investigation was conducted to synthesize and characterize silver nanoparticles using wild edible mushroom extract of Lentinus tuber-regium. The current investigation also aims to determine antimicrobial and α-amylase inhibitory activity of biosynthesized silver nanoparticles (AgNPs). UV–Visible spectrophotometer study indicated that the surface plasmon resonance peak of reaction of AgNPs was around at 433 nm which confirmed the formation of AgNPs. Fourier-transform infrared spectroscopy analysis confirms that carboxyl functional groups in mushroom extract are mainly responsible in reduction of Ag+ ions to Ag0 nanoparticles. Atomic force microscopy, transmission electron microscopy and scanning electron microscopy analysis revealed that synthesized AgNPs were spherical and have an average size within 5 to 35 nm. Selected area electron diffraction and X-ray diffraction pattern displayed that synthesized AgNPs were crystalline in nature. Energy-dispersive X-ray spectroscopy study showed 10.50% of silver metal in weight in the sample. Biosynthesized AgNPs showed more antibacterial activity in Gram (−) bacteria than Gram (+). Minimum inhibitory concentration values of the biosynthesized AgNPs against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Bacillus subtilis were found to be 9, 12, 14 and 13 µg/ml, respectively. Inhibition of α-amylase activity increased with increasing concentration of biosynthesized AgNPs. This work substantially indicates that mushroom is efficient in biosynthesis of silver nanoparticles having potential antimicrobial and α-amylase inhibitory activity.

Exceptional Two-Photon Absorption in Alkynylruthenium-Gold Nanoparticle Hybrids.

Ruthenium alkynyl "star" complexes with tri(2-thienyl)-, tris(1,2,3-triazolyl)-, or triphenyl-benzene cores stabilize gold nanoparticles (AuNPs). Cyclic voltammetry, transmission electron microscopy, molecular modeling, dynamic light scattering, X-ray photoelectron spectroscopy, and energy-dispersive X-ray spectroscopy studies are consistent with ca. 5 trithienyl- or triazolyl-benzene-cored star complexes decorating the exterior of each AuNP. The ca. 2.5 nm diameter (by transmission electron microscopy) trithienylbenzene-cored gold nanoparticle hybrids are significantly less absorbent than classical Brust nanoparticles stabilized by 1-dodecanethiol; with femtosecond pulsed radiation, they exhibit exceptionally strong saturable absorption and two-photon absorption across the visible range and into the near-infrared region (3 000 000 GM at 500 nm and 46 000 GM at 750 nm; 1 GM is equal to 10-50 cm4 s photon-1).

Optoelectronic properties of DNA thin films implanted with titania nanoparticle-coated multiwalled carbon nanotubes

Rendering the unique features of individual nanoscale constituents into macroscopic thin films remains technologically challenging; the engineering of these constituents habitually compromises their inherent properties. Efficient, environmentally benign, and biodegradable DNA and cetyltrimethyl-ammonium chloride-modified DNA (DNA-CT) thin films (TFs) implanted with titania nanoparticle-coated multiwalled carbon nanotubes (MCNT-TiO2) are prepared by a drop-casting technique. The energy dispersive X-ray spectroscopy studies of DNA and DNA-CT TFs with MCNT-TiO2 identifies various elements (C, O, N, P, Na, and Ti) via quantitative microanalysis. The X-ray photoelectron, Raman, Fourier-transform infrared (FTIR), and UV-visible absorption spectra show changes in the chemical compositions and functional groups associated with binding energies, enhancement of characteristic MCNT-TiO2 Raman bands, and intensity changes and peak shifts of the FTIR and UV-Vis-NIR absorption bands, respectively. The PL spectra indicate an energy transfer in the measured samples, and the quenching of PL indicates a decrease in the recombination efficiency. Lastly, we measure the conductivity, which increased with an increasing concentration of MCNT-TiO2 in the DNA and DNA-CT TFs due to the better connectivity of MCNT-TiO2. By using these materials, the optoelectronic properties of DNA and DNA-CT TFs implanted with MCNT-TiO2 are easily tunable, enabling several engineering and multidisciplinary science applications, such as photonics, electronics, energy harvesting, and sensors.

Microstructural characteristics of chitosan deposited az91 magnesium alloy

Magnesium (Mg) and its alloys have been extensively explored as potential temporary implant materials for orthopaedic applications (e.g. Fracture fixation). Magnesium alloy (AZ91) is used for bone implant application since it has lightest structural element, biocompatible, osteoconductive and its mechanical properties are similar to bone. However, they are prone to corrosion in the human body. Hence in order to reduce the corrosion rate and enhance the biocompatibility and biological properties, AZ91 magnesium alloy surface is modified with chitosan layers. Chitosan coating is proposed to decrease the corrosion rate and improve the bioactivity of AZ91 magnesium alloy. In the study, chitosan was coated on the surface of AZ91 magnesium alloy by spin coating technique. The presence of functional group bands of chitosan coating was confirmed using Fourier transform infrared spectroscopy (FTIR).The surface morphology and the grain size of chitosan on AZ91 magnesium alloy substrate was investigated using Field emission scanning electron microscope (FESEM) analysis. The elemental composition of chitosan was confirmed by Energy dispersive X-ray spectroscopy (EDAX) study. The film thickness was also measured for the coated substrate. Thus chitosan is coated on AZ91 magnesium alloy and characterization are done to confirm the presence of chitosan on AZ91 magnesium substrate which can be further tested for its biocompatible properties and used for orthopaedic applications.

Simple Sonochemical Synthesis of Cupric Oxide Sphere Decorated Reduced Graphene Oxide Composite for the Electrochemical Detection of Flutamide Drug in Biological Samples

Reduced graphene oxide/cupric oxide (RGO/CuO) composites were developed by a simple, eco-friendly sonochemical method. This system has been explored as a potential electrocatalyst toward the electrochemical detection of flutamide. The prepared RGO/CuO composite was confirmed by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and Raman spectra studies. In addition, the electrochemical properties of the prepared electrode were investigated by electrochemical impedance spectroscopy, cyclic voltammetry, and chronoamperometry techniques. The RGO/CuO composite modified glassy carbon electrode (GCE) exhibits high electrocatalytic activity toward the detection of flutamide. The RGO/CuO/GCE modified electrode also detects flutamide with a low detection limit (0.001 μM), wide linear range (0.005 to 71.32 μM) and acceptable sensitivity (5.54 μA μM−1cm−2). A fabricated sensor showed good selectivity, repeatability, reproducibility and long-term operational stability. Appreciable recoveries were achieved for the detection of flutamide in water and in biological samples, demonstrating the practical feasibility of the RGO/CuO/GCE modified electrode.

Porous tal palm carbon nanosheets: preparation, characterization and application for the simultaneous determination of dopamine and uric acid.

A novel porous tal palm carbon nanosheet (PTPCN) material was synthesized from the leaves of Borassus flabellifer (tal palm) and used for developing an electrochemical sensor through modifying a glassy carbon electrode (GCE) simply by drop-casting on it a solution of the material for the sensitive simultaneous detection of dopamine (DA) and uric acid (UA), even in the presence of interfering species. The drop-casting solution was prepared by simply dispersing the PTPCNs in ethanol without using any other binding materials (e.g. Nafion). The surface morphologies of the PTPCNs were studied through field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high resolution TEM (HRTEM). Energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction spectroscopy (XPS) studies revealed the chemical composition of the PTPCNs' surface. Their structural properties were studied using X-ray diffraction (XRD) and Raman spectroscopy. Brunauer–Emmett–Teller (BET) analysis confirmed the surface area and pore volume to be 1094.53 m2 g−1 and 0.74 cm3 g−1, respectively, while Barrett–Joyner–Halenda (BJH) pore-size distribution showed the average pore size to be 22 nm. The sufficiently large surface area and pore-size distribution suggested better electrocatalytic properties compared to the average modifying materials. The modified electrode (PTPCNs/GCE) was characterized through impedimetric and CV techniques in standard potassium ferricyanide solution for evaluating their charge-transfer resistance and electrochemical properties. The limits of detection (S/N = 3) were 0.17 μM and 0.078 μM and the sensitivities were 1.2057 μA μM−1 cm−2 and 2.693 μA μM−1 cm−2 for UA and DA, respectively. The possible interactions that took place between the PTPCNs and the analytes that aided in the enhancement of the electroanalytical performance of the PTPCNs/GCE are discussed based on the experimental findings and established theoretical concepts. The PTPCNs/GCE was successfully employed for analyzing real samples, like dopamine injection and urine.

Synthesis of silver nanoparticle with Colocasia esculenta (L.) stem and its larvicidal activity against Culex quinquefasciatus and Chironomus sp

Objective: To synthesize silver nanoparticles with Colocasia esculenta as a reducing agent and to evaluate their effect against Culex quinquefasciatus and Chironomus sp. Methods: The aqueous extract of Colocasia esculenta stem was used for nanosynthesis. The synthesized nanoparticles were characterized by UV-Vis spectrophotometry, Fourier-transform infrared spectroscopy, scanning electron microscope, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and Zeta potential studies. The toxicity of Colocasia esculenta stem extract and the synthesized silver nanoparticles was evaluated against the larval stages of target human filarial vector Culex quinquefasciatus and non-target Chironomus sp. Results: Scanning electron microscopy and transmission electron microscopy studies revealed almost spherical shape of the synthesized silver nanoparticles with size ranging from 13-50 nm. After 24 hours of exposure, the LC50 and LC90 of the plant extract against 4th instars larvae of Culex quinquefasciatus were 745.56 mg/L and 1 258.28 mg/L, respectively, which were higher than those of synthesized silver nanoparticles (5.17 mg/L and 17.32 mg/L after 24 h; 1.58 mg/L and 13.01 mg/L after 48 h). In addition, the LC50 and LC90 of silver nanoparticles against Chironomus sp. were 9.71 mg/L and 23.15 mg/L after 24 h as well as 2.38 mg/L and 19.49 mg/ L after 48 h, respectively. Conclusions: The aqueous stem extract of Colocasia esculenta is a good agent for synthesis of silver nanoparticles, which are almost spherical with size less than 30 nm. The synthesized nanoparticles show good larvicidal activity without any harmful effect on non-target species.

Nanotube structures: material characterization and structural analysis of Ge–Se thin films

Nanotube structures, formed in thin films of chalcogenide glasses open avenues for new applications, since they offer directional options for many effects in these otherwise completely disordered systems. One way to grow nanotubes is through formation of nano-columnar structures by confining them. In this work nano-columnar growth of thermally evaporated GexSe100−x (x = 20, 30, 40) films is achieved through oblique films deposition. The columnar structural organization of the films and its dependence upon the deposition angle and films composition are established by imaging the cross-sectional areas of the films through scanning electron microscopy. Atomic force microscopy, energy dispersive X-ray spectroscopy and Raman Spectroscopy studies reveal respectively variation in the surface porosity, composition changes and structural reorganizations occurring in the films as a function of obliqueness angles and material’s composition. These results are discussed in respect to the structural organization of films deposited under normal flux incidence and deformations and other structural effects caused by films' deposition under variable angles. Based on the experimental results an empirical formula for the tangent rule is suggested which links the incident flux angle α, and the nanotube inclination angle β.

Box-Behnken Design of Experiment Assisted Development and Optimization of Bendamustine HCl loaded Hydroxyapatite Nanoparticles.

Bendamustine HCl, an antineoplastic drug, has a very short life of about 40 minutes which necessitates administration of large doses which leads to increased side effects as well as costs. The present work describes the fabrication, optimization, and evaluation of bioactive hydroxyapatite nanoparticles to achieve sustained delivery of bendamustine HCl. Hydroxyapatite nanoparticles (NPs) were prepared by the wet chemical precipitation method by reacting a calcium and phosphate precursor and the reaction was optimized via Box-Behnken DOE. The drug was loaded on particles by physical adsorption. Various analytical studies were performed on the fabricated nanoparticles in addition to biodistribution studies to establish the physicochemical and biological characteristics of the designed formulation. pH of the reactant solution was found to have a more profound effect on the particle size and size distribution in comparison to reactant concentration. The particles were found to have a spherical morphology by SEM. Size of the blank and drug-loaded nanoparticles was found to be 130±20 nm by TEM. Energy Dispersive X-ray Spectroscopy (EDS) studies confirmed the presence of hydroxyapatite as the dominant phase while DSC studies indicated the presence of the drug in its amorphous form after its adsorption on NPs. Tissue distribution studies further suggested that the majority of drug concentration was released in blood rather than the other organs implying low organ toxicity. Bendamustine loaded hydroxyapatite nanoparticles were successfully optimized and fabricated. Favorable results were obtained in in vitro, in vivo, and analytical studies.

Development and Characterization of Novel Nanostructured SrTi1-xFexO3-y solid solution for Solar Electricity Generation

A novel class of materials namely SrTi1-xFexO3-y or strontium titanate ferrate (STF) with solid solution character, suitable for solar electricity conversion, has been developed. The STF films were prepared by spray pyrolysis technique, designated as 2STF, 3STF and 4STF in the order of increasing thickness. Scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX) and Dark cyclic voltammetry (with and without illumination) studies were performed on the samples. The thicknesses of film deposits on electrodes were also measured by using a DEKTAK 6M STYLUS PROFILER system to compare with the SEM results. A blue LED was used to illuminate the samples by pulsing ‘On’ and ‘Off’ for different time intervals. The SEM images show that the homogeneity of films is directly proportional to the spraying time (thickness). The EDX measurement performed for sample 2STF has confirmed the contents Sr, Ti, and Fe. The XRD results indicate that the STF film compound may contain some material belonging to the perovskite family AMO3, where A and M are metals. The cyclic voltammetry measurements reveal that the developed STF is photochemically active which makes it suitable for solar water splitting application.

Differential antibacterial response exhibited by graphene nanosheets toward gram-positive bacterium Staphylococcus aureus.

Two different morphological forms of graphene nanosheets: improved reduced graphene oxide (IRGO) and modified reduced GO (rGO) (MRGO) have been synthesised by improved and modified methods, respectively. Physical characterisations of these graphene nanosheets were carried out using X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. Colloidal stability of these nanosheets toward a selected bacterium (e.g. Staphylococcus aureus) was ascertained by zeta potential. In the present study, the authors for the first time made an attempt to study and compare the potentialities of these two different forms of graphene nanosheets as efficient bactericidal agents. Field-emission scanning electron microscopy and TEM with energy dispersive X-ray spectroscopy (EDAX) studies of IRGO and MRGO have been carried out to explore their underlying mechanism of antibacterial responses through physical as well as chemical interactions with the selected bacterial species.

The Effect of Boron and Zirconium on the Structure and Tensile Properties of the Cast Nickel-Based Superalloy ATI 718Plus

The effects of boron and zirconium on cast structure, hardness, and tensile properties of the nickel-based superalloy 718Plus were investigated. For this purpose, five alloys with different contents of boron and zirconium were cast via vacuum induction melting and then purified via vacuum arc remelting. Microstructural analysis by light-optical microscope and scanning electron microscope equipped with energy-dispersive x-ray spectroscopy and phase studies by x-ray diffraction analysis were performed. The results showed that boron and zirconium tend to significantly reduce dendritic arm spacing and increase the amount of Laves, Laves/gamma eutectic, and carbide phases. It was also found that boron led to the formation of B4C and (Cr, Fe, Mo, Ni, Ti)3B2 phases and zirconium led to the formation of intermetallic phases and ZrC carbide. In the presence of boron and zirconium, the hardness and its difference between dendritic branches and inter-dendritic spaces increased by concentrating such phases as Laves in the inter-dendritic spaces. These elements had a negative effect on tensile properties of the alloy, including ductility and strength, mainly because of the increase in the Laves phase. It should be noted that the largest degradation of the tensile properties occurred in the alloys containing the maximum amount of zirconium.

Enhanced photocatalytic activity of ternary CuInS2 nanocrystals synthesized from the combination of a binary Cu(I)S precursor and InCl3

Ternary copper indium sulfide (CIS) nanocrystals (NCs) have been synthesized by mixing of binary precursor [CuI(bdpa)2][CuICl2] (1) and/or [CuI(mdpa)2][CuICl2] (2) (where, mdpa and bdpa represent methyl and benzyl ester of 3,5-dimethyl pyrazole-1-dithioic acid, respectively) with InCl3 in a low-temperature solvothermal process. The +1 oxidation state of copper and the atomic ratio Cu to S (1:2) is atomically maintained in the pyrazole-based Cu(I)–S precursor to synthesize phase pure CuInS2. Coordinating solvents like ethylene diamine (EN) and ethylene glycol (EG) have been used in the synthesis without any surfactants. No use of external surfactants in the synthesis of CIS nanoparticles reveals that precursor acts as stabilizing agent. The synthesized nanocrystals were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray spectroscopy (EDX) studies. The optical property of the nanocrystals shows a pronounced quantum confinement effect in the particles with band gap energy ca. 1.5 eV. The formation mechanism of ternary CIS has been proposed. The pore size distributions of the particles show the average pore diameters 13.1 nm from 1 and 5.3 nm from 2. The calculated values of the specific surface area are 8.123 and 9.577 m2/g for 1 and 2, respectively. The excellent photocatalytic degradation of rose bengal (RB) and rhodamine B (RhB) was demonstrated by the porous CIS nanocrystals.