Incorporation Of Ru Research Articles

Ultrasensitive electrochemiluminescence immunosensor based on Ru(bpy)32+ and Ag nanoparticles doped SBA-15 for detection of cancer antigen 15-3

A label-free electrochemiluminescence (ECL) immunosensor based on functionalized Santa Barbara Amorphous-15 (SBA-15) has been developed for detection of cancer antigen 15-3 (CA15-3). The functionalized SBA-15 was prepared by decoration of citrate-capped Ag nanoparticles and incorporation of Ru(bpy)32+on SBA-15. The Ag nanoparticles show remarkable enhancement effect on ECL properties of Ru(bpy)32+. In order to incorporate more Ru(bpy)32+, anionic surfactant sodium dodecyl sulfate (SDS) was used to increase the negative charge of the composite matrix. Chitosan–ionic liquid (CHIT–IL) were also used to increase the conductivity and film stability. The functionalized SBA-15 was used to label the anti-CA15-3 based on the covalent interaction between Ag nanoparticles and the amines of anti-CA15-3. The ECL immunosensor that used to detect breast cancer biomarker CA15-3 exhibits high ECL intensity, good biocompatibility and long-term stability. The results show that the ECL immunosensor has high sensitivity for CA15-3 with a linear range from 0.01U/mL to 100U/mL and a detection limit of 0.004U/mL (S/N=3).

Optical and ferroelectric properties of ruthenium-doped BaTiO3 nanocubes

Structural, optical, dielectric and ferroelectric properties of Ru-doped BaTi1−xRuxO3(x = 0.01, 0.03, 0.05, 0.07, 0.10) nanocubes have been investigated. The average size of nanocube obtained from Rietveld refinement is in the range 35–60 nm. The incorporation of Ru leads to a mixed tetragonal and cubic crystalline phases in doping concentration range 5–7%. Optical band gap changes from 3.2 to 2.74 eV with increase in Ru concentration. Replacement of Ti with Ru quenches band-edge emission and enhances defect emission intensity. Optical absorption and emission spectra have been interpreted in terms of oxygen vacancy. Ruthenium 4d orbital plays a crucial role to improve dielectric constant and diminish ferroelectric Curie temperature. The combined effect of Ru dopant and size gives rise to complex variation of Curie temperature.

Temperature response of luminescent tris(bipyridine)ruthenium(II)-doped silica nanoparticles

Nanoparticle-based temperature imaging is an emerging field of advanced applications. Herein, the sensitivity of the phosphorescence of tris(bipyridine)ruthenium(II)-doped silica nanoparticles towards temperature is studied. 130nm size particles were prepared by a modification of Stöber’s method, that allows the incorporation of Ru[(bpy)3]2+ into the outer particle shell. The entrapped Ru[(bpy)3]2+ retains its photophysical properties, yet the emission of the particles is not affected by the presence of O2, neither by anionic quenchers; quenching by MV2+, on the other hand, is strongly dependent on pH. Between 20 and 60°C, the steady-state emission of the particles decreases linearly with increasing temperature. The slope of the straight line diminishes slightly on thermal cycling, but soon stabilizes. Fluorescence measurements by scanning confocal microscopy indicate that the silica nanoparticles doped with Ru[(bpy)3]2+ can indeed be employed to probe thermal processes in micro-environments.

Removal of elemental mercury with Mn/Mo/Ru/Al2O3 membrane catalytic system

In this work, a catalytic membrane using Mn/Mo/Ru/Al2O3 as the catalyst was employed to remove elemental mercury (Hg0) from flue gas at low temperature. Compared with traditional catalytic oxidation (TCO) mode, Mn/Al2O3 membrane catalytic system had much higher removal efficiency of Hg0. After the incorporation of Mo and Ru, the production of Cl2 from the Deacon reaction and the retainability for oxidants over Mn/Al2O3 membrane were greatly enhanced. As a result, the oxidization of Hg0 over Mn/Al2O3 membrane was obviously promoted due to incorporation of Mo and Ru. In the presence of 8 ppmv HCl, the removal efficiency of Hg0 by Mn/Mo/Ru/Al2O3 membrane reached 95% at 423 K. The influence of NO and SO2 on Hg0 removal were insignificant even if 200 ppmv NO and 1000 ppmv SO2 were used. Moreover, compared with the TCO mode, the Mn/Mo/Ru/Al2O3 membrane catalytic system could remarkably reduce the demanded amount of oxidants for Hg0 removal. Therefore, the Mn/Mo/Ru/Al2O3 membrane catalytic system may be a promising technology for the control of Hg0 emission.

Tunable Energy Transfer Rates via Control of Primary, Secondary, and Tertiary Structure of a Coiled Coil Peptide Scaffold

Herein we report energy transfer studies in a series of Ru(II) and Os(II) linked coiled-coil peptides in which the supramolecular scaffold controls the functional properties of the assembly. A general and convergent method for the site-specific incorporation of bipyridyl Ru(II) and Os(II) complexes using solid-phase peptide synthesis and the copper-catalyzed azide-alkyne cycloaddition is reported. Supramolecular assembly positions the chromophores for energy transfer. Using time-resolved emission spectroscopy we measured position-dependent energy transfer that can be varied through changes in the sequence of the peptide scaffold. High level molecular dynamics simulations were used in conjunction with the spectroscopic techniques to gain molecular-level insight into the observed trends in energy transfer. The most efficient pair of Ru(II) and Os(II) linked peptides as predicted by molecular modeling also exhibited the fastest rate of energy transfer (with k(EnT) = 2.3 × 10(7) s(-1) (42 ns)). Additionally, the emission quenching for the Ru(II) and Os(II) peptides can be fit to binding models that agree with the dissociation constants determined for the peptides via chemical denaturation.

CO2Reforming of CH4over Ru-Substituted Pyrochlore Catalysts: Effects of Temperature and Reactant Feed Ratio

Dry reforming of methane (DRM) was performed on a 1% Ru-substituted lanthanum strontium zirconate pyrochlore, La1.97Sr0.03Ru0.05Zr1.95O7 (LSRuZ), and results were compared to a commercially available 0.5% Ru/Al2O3 catalyst at different bed temperatures and reactant feed ratios. X-ray diffraction of the fresh LSRuZ confirmed the formation of the La2Zr2O7 pyrochlore face-centered crystal lattice using a modified Pechini synthesis procedure. Results from X-ray photoelectron spectroscopy (XPS) on the fresh calcined pyrochlore showed the presence of RuO2, which was also present along with both RuO3 and RuO4 in the 0.5% Ru/Al2O3 catalyst. Temperature-programmed reduction (TPR) showed that Ru was reducible in both catalysts, but the primary TPR peak for Ru reduction was 140 °C higher for the LSRuZ pyrochlore than that for 0.5% Ru/Al2O3, consistent with the incorporation of Ru within the pyrochlore. The effect of the CH4/CO2 feed ratio on the activity was studied by varying the feed ratio as 1:1, 2:1, and 1:2 at ...

Nonenzymatic Amperometric Glucose Sensor Based on Nanoporous Gold/Ruthenium Electrode

AbstractNanoporous gold/ruthenium (npAu‐Ru) nanocomposite catalysts were synthesized by the incorporation of Ru on npAu, which exhibited reasonable nonenzymatic glucose sensing characteristics with good sensitivity and selectivity. The structure and electrocatalytic activities of the npAu and npAu‐Ru catalysts were characterized by transmission electron microscopy, energy dispersive X‐ray spectroscopy and linear sweep voltammetry. To examine the detection of glucose, npAu and npAu‐Ru were loaded on a glassy carbon electrode with chitosan (CHIT) as capping agent for the nanocomposites, GC/npAu/CHIT and GC/npAu‐Ru/CHIT electrode, respectively. The GC/npAu‐Ru/CHIT electrode showed six fold higher sensitivity (240 µA mM−1 cm−2 for the linear dynamic range) for amperometric glucose detection than the GC/npAu/CHIT electrode. This could be attributed to the incorporation of Ru. Moreover the GC/npAu‐Ru/CHIT electrode displayed selectivity for glucose over biological interferents, including ascorbic acid and uric acid.

LaNi 0.9Ru 0.1O 3 as a cathode catalyst for a direct borohydride fuel cell

LaNi 0.9Ru 0.1O 3 as cathode catalyst for a direct borohydride fuel cell (DBFC) was synthesized and investigated for the first time. The electrochemical experiments indicated that perovskite-type oxide LaNi 0.9Ru 0.1O 3 exhibited higher electrochemical performance compared with LaNiO 3, which suggested incorporation of element Ru into LaNiO 3 could further improve the catalytic ability for oxygen reduction reaction (ORR) in alkaline solution. LaNi 0.9Ru 0.1O 3 catalyst was found to have good tolerance of BH 4 −. Meanwhile the maximum power density of 171 mW cm −2 was obtained at 65 °C without using any precious ion exchange membrane. A life test indicated that the DBFC displayed no significant degradation for about 70 h testing. The electrochemical data suggested that LaNi 0.9Ru 0.1O 3, which provided a simple way to construct DBFCs without using any ion exchange membrane, might be promising cathode catalyst with high performance and low cost for DBFCs.

Local structural phenomena in pure and Ru-doped0.9PbZn1/3Nb2/3O3−0.1PbTiO3near the morphotropic phase boundary as revealed by Raman spectroscopy

The development of polar order in perovskite-type (ABO${}_{3}$) solid solutions of relaxors and normal ferroelectrics is studied on the basis of the temperature dependence of polarized Raman spectra of pure and Ru-doped 0.9PbZn${}_{1/3}$Nb${}_{2/3}$O${}_{3}$-0.1PbTiO${}_{3}$ (PZN-0.1PT) single crystals as well as complementary x-ray diffraction analysis. It is shown that the Raman peaks related to Pb-localized vibrations existing solely in a double-perovskite structure (prototype symmetry $\mathit{Fm}\overline{3}m$) are highly sensitive to the nucleation and development of polar atomic arrangements. The doublet near 50 cm${}^{\ensuremath{-}1}$ observed in the high-temperature $\mathrm{Z\ifmmode \bar{}\else \={}\fi{}}(\mathit{XY})Z$ spectra of PZN-$x$PT ($x$ $=$ 0--0.1) is attributed to two distinct cubic states of Pb ions in regions with a local chemical B-site order of the type $\mathrm{Pb}({\mathrm{B}}_{2/3}^{2+}{\mathrm{B}}_{1/3}^{5+}){}_{0.5}{{\mathrm{B}}_{0.5}}^{5+}{\mathrm{O}}_{3}$: Pb1 ions surrounded mainly by Nb${}^{5+}$ and Pb2 ions surrounded by both Zn${}^{2+}$ and Nb${}^{5+}$. The singlet in the high-temperature $\mathrm{Z\ifmmode \bar{}\else \={}\fi{}}(\mathit{XY})Z$ spectra is assigned to off-centered Pb2 ions. The Raman spectra of PZN-0.1PT indicate that off-centered Pb2 ions induce coherent polar shifts of ferroelectrically active B cations, which in turn facilitates the off-centering of Pb1 ions. A low degree of B-site doping with mixed-valence elements like Ru can substantially influence the development of ferroelectric order in PZN-$x$PT solid solutions due to the different preferred types of local octahedral distortion associated with the different valence states of the doping cations. The incorporation of Ru into the structure of PZN-0.1PT slightly decreases the Burns temperature and shifts the tetragonal-to-monoclinic phase transition to lower temperatures, thus favoring the tetragonal state in a wider temperature range as compared to the undoped compound. An assumption is made that the nanoscale polar order in Pb-based B-site complex perovskite-type relaxors might be of ferrielectric type rather than of ferroelectric type.

Fission products stability in uranium dioxide

Fission product stability in nuclear fuels is investigated using density functional theory (DFT). In particular, incorporation and solution energies of He, Kr, Xe, I, Te, Ru, Sr and Ce in pre-existing trap sites of UO 2 (vacancies, interstitials, U–O divacancy, and Schottky trio defects) are calculated using the projector-augmented-wave method as implemented in the Vienna ab initio simulation package. Correlation effects are taken into account within the DFT+U approach. The stability of many binary and ternary compounds in comparison to soluted atoms is also explored. Finally the involvement of FP in the formation of metallic and oxide precipitates in oxide fuels is discussed in the light of experimental results.

Dibenzothiophene hydrodesulfurization over Ru promoted alumina based catalysts using in situ generated hydrogen

Catalytic hydrodesulfurization (HDS) of dibenzothiophene (DBT) was carried out in a temperature range of 320–400 °C using in situ generated hydrogen coupled with the effect of selected organic additives for the first time. Four kinds of alumina based catalysts i.e. Co–Mo/Al 2O 3, Ni–Mo/Al 2O 3, Ru–Co–Mo/Al 2O 3 and Ru–Ni–Mo/Al 2O 3 were used for the desulfurization process, which were prepared following incipient impregnation method with fixed metal loadings (wt.%) of Co, Ni, Mo and Ru. The surface area, average pore diameter and pore volume distribution of the fresh and used catalysts were measured by N 2 adsorption using BET method. Catalytic activity was investigated in a batch autoclave reactor in the complete absence of external hydrogen gas. Addition and mutual reaction of specific quantities of water and ethanol provided the necessary in situ hydrogen for the desulfurization reaction. Organic additives like diethylene glycol (DEG), phenol, naphthalene, anthracene, o-xylene, tetralin, decalin and pyridine did impinge the HDS activity of the catalysts in different ways. Liquid samples from reaction products were quantitatively analyzed by HPLC technique while qualitative analyses were made using GC–MS. Both of these techniques showed that Ni-based catalysts were more active than Co-based ones at all conditions. Moreover, incorporation of Ru to both Co and Ni-based catalysts greatly promoted desulfurization activity of these catalysts. DBT conversion of up to 84% was achieved with Ru–Ni–Mo/Al 2O 3 catalyst at 380 °C temperature for 11 h. Catalyst systems followed the HDS activity order as: Ru–Ni–Mo/Al 2O 3 > Ni–Mo/Al 2O 3 > Ru–Co–Mo/Al 2O 3 > Co–Mo/Al 2O 3 at all conditions. Cost effectiveness, mild operating conditions and reasonably high catalytic activity using in situ generated hydrogen mechanism proved our process to be useful for HDS of DBT.

A Multilayer Film for Bifunctional Electrocatalyst and Electrochemical Sensor Based on Polyoxometalate and Tris(1,10-Phenanthroline)Ruthenium

The multilayer films containing tris(1,10-phenanthroline) ruthenium(II) Ru(phen)3Cl2 (abbr. Ru(phen)3, phen = 1,10-phenanthroline) and polyoxometalate [P2W18O62]6− (abbr. P2W18) through a layer-by-layer (LBL) process were fabricated. UV–vis absorption spectra showed that the subsequent growth of the multilayer film was regular and highly reproducible from layer to layer. X-ray photoelectron spectra (XPS) confirmed the incorporation of Ru(phen)3 and P2W18 into the film. The result of atomic force microscopy (AFM) revealed a relatively uniform surface morphology of the multilayer film. The multilayer film exhibited remarkable electrocatalytic activities toward the reduction of $$ {\text{IO}}_{3}^{ - } $$ and the oxidation to l-cysteine. The value of I pc was as a function with the concentration of iodate and l-cysteine, which indicated that the film can be a candidate for bifunctional electrocatalyst and electrochemical sensor.

Surface Modification of Sputtered Ga.<sub<5</sub>In.<sub>5</sub>Sb hin Films

Growth of Ga.5In.5Sb thin films was carried out using a in a r.f. magnetron sputtering system on high-purity quartz glasses as a substrate. The target material for the film was grown in the laboratory using Vertical Bridgmen method. The polycrystallinity of the sputtered films were characterized using x-ray diffraction method. Thegrown films were then treated with Ruthenium (Ru), Platinum (Pt) and Palladium (Pd) ions. XPS studies on the film showed the incorporation of Ru, Pt and Pd along with Ga, In and Sb. However in case of Ru and Pt treated surface a mild oxygen peak was also observed. No such oxide peak was observed in Pd treated surface. SEM studies on the filmswere also carried out which shows the increase in smoothness of the film after Ru and Pt treatment, whereas the surface deteriorated in case of Pd treatment. This can be interpreted as reduction in surface states induced by passivating oxide formed after Ru and Pt treatment. Electrical characterization of the film viz. Vander Pauw resistivity, Hall mobility etc. measurements also showed improved result compared to untreated and Pd treated surface and is been reported. Finallywith chemically treated films Au/Ga.5In.5Sb Schottky diodes were fabricated and electrically characterised for IR detectors.

Enhancement of adhesion strength and corrosion resistance of nitrogen or platinum/ruthenium/nitrogen doped diamond-like carbon thin films by platinum/ruthenium underlayer

A platinum/ruthenium (PtRu) underlayer was grown on highly conductive p-Si (100) substrates, on which nitrogen doped diamond-like carbon (N-DLC) thin films without or with incorporation of Pt and Ru (PtRuN-DLC) were deposited, both via a DC magnetron sputtering system. The effect of PtRu underlayer on the bonding structure, surface morphology and adhesion strength of the N-DLC and PtRuN-DLC films was investigated using X-ray photoelectron spectroscopy (XPS) and micro-Raman spectroscopy, atomic force microscopy (AFM) and micro-scratch testing, respectively. The effect of the PtRu underlayer on the corrosion performance of these films in a 0.1 M HCl solution was diagnosed using electrochemical impedance spectroscopy (EIS). Although the incorporation of Pt and Ru into the N-DLC films promoted sp 2 sites in the films via metal-induced graphitization, the PtRu underlayer along with the incorporation of Pt and Ru in the N-DLC films could enhance the charge transfer resistance of the films, indicating the increased corrosion resistance of the films.

Catalytic upgrading of biomass fast pyrolysis vapors with titania and zirconia/titania based catalysts

Fast pyrolysis of poplar wood followed with catalytic upgrading of the pyrolysis vapors was performed using analytical pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS). The catalysts applied in this study were three commercial meso- or macroporous catalysts (TiO 2 (Rutile), TiO 2 (Anatase) and ZrO 2&TiO 2) and their modified ones with incorporation of Ce, Ru or Pd. These catalysts displayed different catalytic effects on the pyrolytic products. The TiO 2 (Rutile) based catalysts, especially the Pd/CeTiO 2 (Rutile), were effective to convert the lignin-derived oligomers to monomeric phenolic compounds, with the phenols increasing from 25.6% in the non-catalytic products to 37.2% after catalyzed by the Pd/CeTiO 2 (Rutile). The ZrO 2&TiO 2 based catalysts were the most effective to change the pyrolytic products. They significantly reduced the phenols, acids and sugars, and meanwhile, increased the hydrocarbons, linear ketones and cyclopentanones. The highest hydrocarbon content of 13.1% was obtained by the ZrO 2&TiO 2, compared with only 0.1% in the non-catalytic products. The catalytic effects of the TiO 2 (Anatase) based catalysts were between that of the TiO 2 (Rutile) and ZrO 2&TiO 2 based catalysts.

Visible-light hydrogen generation using as photocatalysts layered titanates incorporating in the intergallery space ruthenium tris(bipyridyl) and methyl viologen

A series of layered titanates containing in the interlayer space tris(2,2′-bipyridyl)ruthenium(II) [ Ru ( bpy ) 3 2 + ] or methyl viologen (MV 2+) or both has been prepared and characterized by elemental analyses, XRD, and optical and vibrational spectroscopy. Incorporation of Ru ( bpy ) 3 2 + and MV 2+ is confirmed by the increase of the distance between the titanate layers. The presence of Ru ( bpy ) 3 2 + in the material is also revealed in optical spectroscopy where the ligand to metal charge transfer band appearing at λ max 460 nm is observed. Also incorporation of MV 2+ leads to the observation of the charge transfer complex band with the titanate host from 350 to 650 nm. These solids are active for the photocatalytic hydrogen generation from water when colloidal platinum as catalyst and EDTA as sacrificial electron donor are present in the solution. The maximum efficiency was obtained for a solid consisting of layered titanate containing a 10.2 wt.% loading of Ru ( bpy ) 3 2 + incorporated in the titanate layers and MV 2+ and Pt nanoparticles in the aqueous solution. This heterogeneous system produced about one-half the hydrogen generated for the conventional homogeneous system where all the components [ Ru ( bpy ) 3 2 + , MV 2+, Pt, and EDTA] are in solution, with the advantage that it can be used as film or recovered by filtration from the aqueous medium.

Permselective properties of polystyrene opal films at diamond electrode surfaces

The permselective properties of stable opal films formed by polystyrene nanospheres on boron-doped diamond (BDD) electrodes were studied for the first time by means of electrochemical voltammetric and impedance techniques. Films formed from spheres with a diameter above 200 nm are highly porous and have little influence on electrochemical properties. In contrast, porous films formed from 50 nm spheres have a selective influence on the electrochemistry observed, providing an enhancement in the redox peak current for neutral (ferrocenemethanol, dopamine) and positively-charged redox probe mediators (Ru(NH(3))(6)(3+)) and suppressing the current due to a negatively-charged redox species Fe(CN)(6)(4-). This is because the latter is repelled from the film, whereas the former are selectively partitioned within it. Partition coefficients, film permeability and diffusion coefficients of species within the polystyrene opal layer are determined. It is shown that a Langmuir isotherm analysis for adsorption on the polystyrene sphere surface can describe successfully the incorporation of ferrocenemethanol and Ru(NH(3))(6)(3+) within the thin film, with Gibb's free energies (DeltaG(o)) of adsorption in the range of -27 to 28 kJ mol(-1). Apart from influencing the magnitude of the detected electrochemical response, it is also shown the opal film increases the resistance to electrode fouling by the reaction products formed by the oxidation of dopamine. Electrochemical impedance measurements further illustrate the effects of the polystyrene layer.

Ferroelectric properties of ruthenium-doped lead zinc niobate-lead titanate single crystal

Using atomic force microscopy and piezoresponse force microscopy (PFM), as well as complementary dielectric measurements, the ferroelectric domain structure of single crystals of pure and ruthenium (Ru)-doped 0.9Pb(Zn1/3Nb2/3)O3 (PZN)-0.1PbTiO3 (PT), and Ru/(Zn+Nb+Ti)∼0.002 was analyzed. The coexistence of tetragonal and nontetragonal ferroelectric domains in PZN-PT near the morphotropic phase boundary (MPB) was directly observed via PFM imaging. The incorporation of Ru in the perovskite structure substantially decreases the ferroelectric domain size, thus reducing the polar fraction distributed in the pseudocubic matrix. The polarization and strain hysteresis loops show that Ru doping leads to significant ferroelectric hardening, which is attractive for high-power applications. The local structure and valent state of the incorporated Ru cations were additionally analyzed by electron paramagnetic resonance spectroscopy. Our results demonstrate that doping of tetragonal PZN-PT near MPB is a promising route to design advanced multifunctional single-crystal materials.

Structure and corrosion behavior of platinum/ruthenium/nitrogen doped diamondlike carbon thin films

Platinum/ruthenium/nitrogen doped diamondlike carbon (PtRuN-DLC) thin films were deposited on p-Si (100) substrates with dc magnetron cosputtering by varying the dc power applied to a Pt50Ru50 target to investigate the effect of Pt and Ru incorporation in the films on the bonding structure, adhesion strength, surface morphology, and corrosion behavior of the films by means of X-ray photoelectron spectroscopy, micro-Raman spectroscopy, microscratch test, atomic force microscopy, scanning electron microscopy, and potentiodynamic polarization test. It was found that the incorporation of Pt and Ru in the N-DLC films improved the corrosion resistance of the films in a 0.1M NaCl solution at lower polarization potentials though more sp2 bonds were formed in the films. However, the films with higher Pt and Ru contents degraded earlier than the ones with lower Pt and Ru contents at higher polarization potentials.

Investigations on Ru doped ZnO: Strain calculations and gas sensing study

Pure and ruthenium (Ru) doped nano-crystalline zinc oxide (ZnO) powders were synthesized by using well-known citrate gel route. Citric acid acts as a chelating agent and thus helps in the formation of nanoparticles. The detailed X-ray diffraction (XRD) studies using Hall equation reveal that in the nanoscale dimensions, incorporation of Ru modulates the lattice strain. It is interesting to note that on Ru doping, the compressive strain present in the undoped ZnO changes into tensile strain. We have tested the response of these specimens individually for reducing gases like H 2, LPG (liquefied petroleum gas), C 2H 5OH (ethanol), CO, acetone and oxidizing gases like NO x and Cl 2. Undoped ZnO responses perceptibly to LPG while Ru doped sample highly senses ethanol vapors. This might be due to either change in composition on Ru doping or/and difference between basicity of LPG and C 2H 5OH vapors.