Template Synthesis Method Research Articles

SRIM Simulation of Carbon Ions Interaction with Ni Nanotubes

By template synthesis method nickel nanotubes with diameter of 400 nm and length of 12 μm were produced in the pores of PET template. The nanotubes were modified by irradiation with carbon ions with energy of 28 MeV and a dose of 5 × 1011 cm-2. To ensure the maximum efficiency of nanostructures modification process, energy of irradiation was decided by using of SRIM software. Based on SRIM simulation of carbon ions interaction with Ni nanotubes, the areas on which effect of high energy ions will maximum were predicted. A comparative analysis of nanostructures before and after irradiation was carried out by scanning electron microscopy. The maximum change in nanotubes morphology, in the form of destruction of walls, was appeared at a distance of about 10 μm from the start point of C3+ ions track inside the nanotubes. A substantiation of reason of wall degradation in this area was proposed

Photocatalytic Performance of H6 P2 W18 O62 /TiO2 Nanocomposite Encapsulated into Beta Zeolite under UV Irradiation in the Degradation of Methyl Orange.

In this work, neat and supported H6 P2 W18 O62 into nanocage of β-zeolite were synthesized. However, H6 P2 W18 O62 into nanocage of β-zeolite was synthesized via template synthesis method. In addition, TiO2 was supported on H6 P2 W18 O62 /β zeolite by impregnation method. The obtained materials were characterized by XRD, FT-IR, UV-Vis, FESEM and EDS techniques. Also, W and Ti contents of the catalyst were determined by ICP and EDS technique. The results reveal that the photocatalyst performance depends on catalyst loading, pH effect, and methyl orange concentration. Photocatalytic degradation of methyl orange follows a pseudo-first order kinetic. The chemical oxygen demand (COD) experimental proved mineralization of methyl orange. Another reason for degradation and mineralization of methyl orange is the absence of hydrazine at the end of reaction which is one of the photodecolorization products. The plausible mechanism for photodegradation of MO was proposed.

FeCo nanotubes: possible tool for targeted delivery of drugs and proteins

Progress in biomedicine leads to the appearance of novel methods of treatment at both the molecular and cellular scales. This treatment requires the nanoscale materials, capable to affect locally being manipulated from outside. Magnetic nanotubes (NTs) are the promising tool for a variety of bioapplications, including targeted delivery driven by a magnetic field, magnetic resonance imaging, magnetic separation. In this work, the Fe- and Co-doped NTs were synthesized by a template synthesis method in pores of polyethylene terephthalate membranes. The structural and magnetic properties of the obtained FeCo NTs were investigated. In comparison with well-established nanowires, the FeCo NTs demonstrated some advantages such as the homogeneous magnetic field, lower density, and larger specific surface area. A simple way for functionalization of the FeCo NTs with polymethylmethacrylate for targeted delivery of drugs is proposed. The model scheme of drugs attachment to the surface of NTs has been developed and the binding process was illustrated with cyclodipeptide.

ZnS-based dual nano-semiconductors (ZnS/PbS, ZnS/CdS or ZnS/Ag2S,): A green synthesis route and photocatalytic comparison for removing organic dyes

Organic dyes generating from many industries are considered as a potential source of water-pollution and have negative effects on human health. The present study was aimed to construct a green synthesis method for fabrication of ZnS-based dual nano-semiconductors and to compare the photocatalytic properties for removing cationic and anionic dyes. ZnS nanoparticles were synthesized using a template synthesis in bovine serum albumin (BSA) solution and then ZnS/PbS, ZnS/CdS and ZnS/Ag2S dual nano-semiconductors were prepared using ion-exchange method. Prepared nano-semiconductors were characterized by using HR-TEM, XRD, FTIR, TG/DTA and AAS. Moreover, photocatalytic activity of prepared nano-semiconductors was tested against Rhodamine B (cationic dye) and Methyl Orange (anionic dye). Results revealed that a controllable ZnS/PbS, ZnS/CdS and ZnS/Ag2S ratio in nano-semiconductors can be achieved by adjusting the ion-exchange time. Prepared ZnS based composites exhibited higher photocatalytic efficiency than that of ZnS alone. In addition, photocatalytic activity of ZnS-based dual nano-semiconductors was found to be dependent upon composition and ratio of sulphides in nano-semiconductors with environmental pH. It was concluded that the combination of template synthesis and ion-exchange method is a feasible approach to fabricate new photocatalysts with higher photocatalytic activity.

INVESTIGATION OF STRUCTURAL PROPERTIES OF FexNi100-x NANOTUBES

The paper presents the results of studying the structural properties of polycrystalline FexNi100-x nanotubes obtained by the template synthesis method. The nanostructures represent nanotubes with a high degree of polycrystallinity of Fe100-xNix with a body-centered cubic structure for 0 £ x £ 0.4, and with face-centered cubic structure for 0.5 £ x £ 0.9. Mechanisms for the synthesis of nanostructures with a specified phase composition and crystal structure have been established. It was found that Fe100 nanostructures possess the lowest degree of crystallinity, which is caused by a high degree of disorder of the crystal structure during the formation of iron nanostructures under given synthesis conditions. An increase in the concentration of nickel leads to a substantial decrease in the degree of disorder of the nanotubes and to the perfection of the crystal structure.

Specific Features of Obtaining of Metal Nanowires by Replication of Pores of Track Etched Membranes

Ensembles (massives) of metal nanowires (with diameters 50-200 nm) were obtained using method of template synthesis. Polymer track etched matrixes were used as template. Nanowires obtained were the replicas of the pores in these membranes. The problems of choosing of electrolyte and different regimes of electrodeposition were discussed. Different techniques of separation of obtained nanowires from growth polymer matrix were used-etching at elevated temperature, ultrasound and UV-treatment. The regimes of obtaining of layer Cu/Ni nanowires were investigated and the optimal voltages were found: 0.8 V for Cu-layer and 1.8 for Ni layer. It was also found that application of magnetic field accelerate the process of electrodeposition; moreover, application of SOUTH pole leads to formation of hollow Ni-layers. Using of “two-bath” method of electrodeposition found to be optimal for obtaining of two-parts wires. Such wires could be used for generation of THz irradiation.

Investigation of the electrochromic properties of Ni(OH)2 films on glass with ITO­Ni bilayer coating

Electrochromic films have been deposited onto glass coated with indium-tin oxide (ITO) and glass with ITO and a thin layer of metallic nickel deposited onto it. Nickel was deposited onto the surface of the ITO coating from nickel electroplating solution. The metallic nickel was deposited onto the surface of ITO at the following parameters – cathodic current density 0.5 A/dn 2 , deposition time 3 s. Such deposition parameters were chosen, because at longer deposition time and (or) higher current density, the deposited layer of metallic nickel became opaque. The two substrates were then used in the deposition of Ni(OH) 2 electrochromic films using the cathodic template synthesis method. As a result, it was revealed that the electrochromic film deposited onto glass with ITO-Ni coating possesses higher specific characteristics than that deposited on bare ITO-coated glass: higher coloration degree and higher oxidation-reduction currents on the cyclic voltamperogram. However, it was also revealed that the film possessing better characteristics, on the contrary, has lower reversibility of the coloration-bleaching process. Based on the obtained data, the mechanism that explains the role of the intermediate metal layer was proposed. The mechanism is that the deposited layer of metallic nickel forms additional contacts between the substrate surface and the electrochromic film. The nickel layer can also assist in securing the electrochromic film, and during film deposition has a positive effect on current distribution. On the other hand, the lower reversibility of the coloration-bleaching process of the film on ITO-Ni coating can be explained by gradual oxidation of metallic nickel in the basic medium. At the same time, it was revealed that deposition of metallic nickel leads to some decrease of the substrate transparency.

Label-Free Detection of Salivary Pepsin Using Gold Nanoparticle/Polypyrrole Nanocoral Modified Screen-Printed Electrode.

Detection of salivary pepsin has been given attention as a new diagnostic tool for laryngopharyngeal reflux (LPR) disease, because saliva collection is non-invasive and relatively comfortable. In this study, we prepared polypyrrole nanocorals (PPNCs) on a screen-printed carbon electrode (SPCE) by a soft template synthesis method, using β-naphthalenesulfonic acid (NSA) (for short, PPNCs/SPCE). Gold nanoparticles (GNPs) were then decorated on PPNCs/SPCE by electrodeposition (for short, GNP/PPNCs/SPCE). To construct the immunosensor, pepsin antibody was immobilized on GNP/PPNCs/SPCE. Next, citric acid was applied to prevent non-specific binding and change the electrode surface charge before pepsin incubation. Electrochemical stepwise characterization was performed using cyclic voltammetry, and immunosensor response toward different pepsin concentrations was measured by differential pulsed voltammetry. As a result, our electrochemical immunosensor showed a sensitive detection performance toward pepsin with a linear range from 6.25 to 100 ng/mL and high specificity toward pepsin, as well as a low limit of detection of 2.2 ng/mL. Finally, we quantified the pepsin levels in saliva samples of LPR patients (n = 2), showing that the results were concordant with those of a conventional ELISA method. Therefore, we expect that this electrochemical immunosensor could be helpful for preliminarily diagnosing LPR through the detection of pepsin in saliva.

Effect of SHI on properties of template synthesized Cu nanowires

Metallic as well as semiconducting nanostructures have generated wide interest and are achieving growing importance because of their potential applications in various devices, such as batteries, manufacturing of electrical contacts in microelectronics, MEMS, and solar cells. In the present work, template synthesis method coupled with electrodeposition has been used to synthesize copper nanowires of diameter 200 nm into the pores of a polycarbonate track-etched (PCTE) membrane. The synthesized Cu nanowires were irradiated with 150-MeV Ti9+ swift heavy ions at Inter University Accelerator Centre (IUAC), New Delhi, India. The pristine and irradiated nanowires were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive spectroscopy (EDS), and Keithley 2400 series source meter to study their structural, morphological, elemental, and electrical properties, respectively. XRD analysis confirmed the face-centered cubic crystal system for pristine as well as irradiated samples. The lattice strain and crystallite size were evaluated using line broadening analysis methods following modified Scherrer method. Theoretical calculations have been done to obtain Young’s modulus of the nanowires and that has further been used to evaluate stress generated in the nanowires. Hall-Petch relation has been used to evaluate the change in strengthening coefficient in the nanowires due to irradiation. SEM analysis confirmed the cylindrical morphology of wires with a uniform diameter throughout the complete length of the wires. A change in electrical conductivity of the nanowires has been observed with increase in the fluence which is attributed to change in the orientation of grain boundaries and formation of defects.

A macrocyclic cavity microenvironment strategy for protecting lanthanide emitters from quenchers in solution

Here we report the new insight into lanthanide complexes with “shell-type” protection by the natural macrocyclic cavity. A family of mononuclear Ln(III) complexes 1–6 based on a 21-membered [1 + 1] Schiff-base macrocyclic ligand H2L, originating from extended dialdehyde H2pdd and 1,2-bis(2-aminoethoxy)ethane precursors, have been obtained by the template synthesis method. Crystal structure analysis reveals that each Ln(III) ion, coordinated to one macrocycle H2L and two nitrates, is successfully capsulated by macrocyclic cavity forming the “lasso-type” architecture. Meanwhile, the photophysical measurements are studied for all six complexes in CH3OH, showing characteristic luminescence peaks of the Sm(III) ion in the visible band range for complexes 3 which are attributed to efficient energy transfer from macrocyclic sensitizer H2L. This strong luminescence of Sm(III) complex 3 is also quantitatively evidenced and its quantum yield is as high as 0.35% in CH3OH at room temperature. Comparing other reported examples these lanthanide complexes support another reliable method to shield Ln(III) ions from quenchers.

Formation of (Cu)<sub>n</sub> & (Cu<sub>2</sub>O)<sub>n</sub> nanostructures with the stability of their clusters

We investigated the electronic structure and the properties of cupper (Cu) and compound semiconductor (Cu2O) by with the help of computer simulation of the programs developed by us and obtaining various morphologies and properties of Cu nanostructures by the method of template synthesis, including the study of the direction of formation processes and the practical application of ion tracks. In calculations of the computer simulation programs developed by us, the general and area-predicted density of states and the band dispersion of optimized crystal structures with different structural units (Cu)n (n = 6, 12) and (Cu2O)n (n = 16, 23) were described. Accordingly, this leads to the prediction that (Cu)n at n = 12 and (Cu2O)n at n = 23 take a high electron density, and that the energy maximum points arise where there is a low electron density and, conversely, for electron energy minima, the electron density is high. The maxima of the level energy n = 2 for (Cu)n and (Cu2O)n, the corresponding electron densities also reached their maximums, but these values of the metallic and semiconductor junctions, respectively, were sharply different in value when compared with each other. This indicates that the changes in the electronic states were due mainly to the replacement of the oxygen atom and subsequent modification of the crystalline field.

Effects of indigo carmine concentration on the morphology and microwave absorbing behavior of PPy prepared by template synthesis

In the study, a series of polypyrrole (PPy) samples were prepared by a method of template synthesis at different indigo carmine (IC) concentrations while keeping the amount of pyrrole and FeCl3 as well as the reaction conditions unchanged. Effects of IC concentration (MIC) on the morphology, conductivity and microwave absorbing behavior of the obtained PPy products were investigated. The results showed that the morphology of PPy transformed from granular flocking to rods and then to spiral rods as MIC increased from 0.05 to 7.50 mM, and the morphology transformation mechanism of PPy was attributed to the structural transformation of IC micelles caused by the change of MIC. The conductivity of PPy was also found to be influenced by MIC. Further investigation indicated that the spiral rod-shaped PPy (S-5) showed obviously superior microwave absorbing behavior compared with that of the granular flocking shaped PPy or that of the rod-shaped PPy, which was attributed to the benefits of its spiral structure and the comparably higher dielectric loss resulted from its lower conductivity.

Fe-N-doped porous carbon from petroleum asphalt for highly efficient oxygen reduction reaction

Fe-N-doped porous carbon derived from petroleum asphalt (NPCA) was prepared via a facile template synthesis method, with urea as nitrogen source while α-Fe2O3 nanoparticles as template and Fe source. The as-prepared NPCA calcined at 900 °C (NPCA-900) exhibits excellent electrocatalytic performance with high diffusion-limiting current density and stability comparable to those of commercial Pt/C catalysts in alkaline environment. The remarkable ORR performance of NPCA could be ascribed to the abundant porosity, large specific surface area (1060 m2 g−1), as well as the doping of Fe-N (especially pyridinic N). The NPCA derived from cheap petroleum asphalt has good application future in the field of catalysis, while it may pave a new way to realize the clean and high value utilization of heavy oils.

Morphology design of microporous organic polymers and their potential applications: an overview

Microporous organic polymers (MOPs) have attracted considerable research interest because of their well-defined porosity, high surface area, lightweight nature, and tunable surface chemistry. The morphology of MOPs are demonstrated to play a significant role in various applications although limited examples manifesting the importance of the MOP morphology in numerous applications have been reported. This review summarizes the recent progress in the design of MOPs using different techniques, including hard and soft template and direct synthesis methods. In addition, their applications, which possibly attribute to their shape, are discussed. Furthermore, the advantages and disadvantages of different methods are discussed, as well as their development and future challenges.

Template synthesis of imine-based covalent organic framework core-shell structure and hollow sphere: a case of COFTTA-DHTA

Controllably synthesizing well-dispersed covalent organic frameworks (COFs) with uniform both morphology and size is still a challenge. Herein, we report the template-directed synthesis of COFTTA-DHTA-based core-shell hybrids under solvothermal conditions by using amino-functionalized SiO2 microspheres as templates coupled with stepwise addition of initial monomer molecules. The modified amino groups on the surfaces of SiO2 templates play an important role in the formation of well-defined NH2-f-SiO2@COFTTA-DHTA core-shell hybrids. COFTTA-DHTA hollow spheres can be obtained by etching SiO2 cores of NH2-f-SiO2@COFTTA-DHTA. Both the NH2-f-SiO2@COFTTA-DHTA and COFTTA-DHTA hollow spheres possess the well-defined morphology, high crystallinity and porosity, excellent dispersion property and high chemical stability. The template synthesis method demonstrated in this work provides a general method for the shape-controlled synthesis of COF-based materials, which is important for the further applications in the fields such as energy storage, drug delivery and catalysis.

Growth mechanisms of spatially separated copper dendrites in pores of a SiO2 template

n-Si/SiO2(Cu) structures with different morphologies of copper deposits are produced using the template synthesis method. Deposition of Cu nanostructures and their structural features is thoroughly studied, and mechanisms for the formation of compact and dendrite-like deposits in the pores of the SiO2 template on the n-type single-crystal silicon substrate are established. Spatially separated copper dendrites are obtained and used to investigate the efficiency of Raman scattering enhancement using the aqueous solution of the Rhodamine 6G dye.

Impact of the crystallinity of mesoporous polymeric graphitic carbon nitride on the photocatalytic performance under UV and visible light

Mesoporous polymeric graphitic carbon nitrides (mpg-C3N4) were prepared by combined soft templated solvothermal synthesis method and detailed post-thermal treated starting from low temperature. The materials were structurally characterized by powder X-ray diffraction and ATR-FTIR spectroscopy. The morphology and texture of the samples were studied by TEM, STEM and nitrogen adsorption desorption isotherm measurements. The photocatalytic activity was tested in the degradation of the harmful and recalcitrant pharmaceutical pollutant ibuprofen. New photocatalytic results were obtained by testing the degradation at low catalyst content and low catalyst to substrate ratio of four under sun light equivalent UV and visible room light. The mineralization of the organics to carbon dioxide and water was followed by TOC measurements. The formation of reaction intermediates was further checked by ESI-TOF-MS measurements. Highly active mesoporous polymeric pure mpg-C3N4 photocatalysts were obtained. It was found that the crystallinity of the mpg-C3N4 has a pronounced impact on the photocatalytic activity. Especially, post-synthesis low temperature exposure led to complete loss of the photocatalytic activity. Therefore, the pretreatment had a decisive effect on the final photocatalytic performance. The scavenger experiments showed that super oxide radical anions and hydroxyl radicals were the active reactive oxidative species with mesoporous polymeric carbon nitride. Mpg-C3N4 is a “green” photocatalyst because the number of formed by-products is limited.

Benchmark comparison of Co3O4 spinel-structured oxides with different morphologies for oxygen evolution reaction under alkaline conditions

In this work, a series of Co3O4 spinels were produced by different synthesis routes (precipitation, solution combustion synthesis, and hard template method), and were used as non-noble catalysts for the oxygen evolution reaction (OER) under basic conditions. The investigated catalysts have a proportional relation between electrochemical activity, surface roughness, and specific surface area. The hard template synthesis method resulted in the most active catalyst compared in this work, which we ascribe to its highly porous structure, and concomitant Co3+/Co4+ redox couple at a lower potential, attributed to the OER. The most performant catalyst was compared with a commercial catalyst (Ni@NiO, Alfa Aesar) showing only 0.01 V overpotential difference, evaluated at 10 mA cm− 2 (overpotential 0.44 V).

Ultra-sensitive determination of insulin on pencil graphite electrode modified by cerium salen encapsulated zeolite (CS@Z-PGE)

In this study, cerium salen encapsulated into dealuminated zeolite Y (CS@Z) was prepared through template synthesis method. This heterogeneous catalyst was characterized by XRD, FT-IR, SEM and EDS analysis. The amount of CS in the nanocage of zeolite was obtained 0.0846 g/g of support. Pencil graphite electrode modified by CS@Z was applied for electrochemical ultra-sensitive determination of insulin. Parameters influencing the method were optimized. A linear range calibration curve from 0.05 to 50 nM of insulin with a detection limit of [12.8 (±0.6) pM] (based on S/N = 3) and sensitivity of [44.3 (±0.8) μA μM−1] was observed at pH 7.4 and applied potential of 0.45 V by amperometry. The results demonstrated that the sensor can be used for the determination of insulin in the commercially available injections.

Synthesis Characterization and Investigation of Photocatalytic Activity of H3PMO12O40/TiO2/HY Nanocomposite for Degradation of Methyl Orange in Aqueous Media

Molybdophosphoric acid encapsulated into dealuminated zeolite Y (DAZY) was prepared by template synthesis method. Incorporation of TiO2 into nanocage of DAZY was performed by impregnation method. The obtained photo catalyst (HPA/TiO2/DAZY) was characterized by FT-IR, UV–Vis, FESEM, XRD, EDS and ICP technique. This catalytic system was investigated in the photodegradation of methyl orange. The obtained results reveal that the photo catalyst performance depends to photo catalyst loading and TiO2/(HPA/HY) ratio. The photocatalytic activity of molybdophosphoric acid encapsulated into zeolite cage enhanced with impregnation of TiO2 into nanocage of dealuminated Y zeolite so that complete removal of methyl orange was occurred.