Bimetallic AgFe Systems on Mordenite: Effect of Cation Deposition Order in the NO Reduction with C3H6/CO

Mono- and bimetallic systems of Ag, Fe, and Ag–Fe exchanged in sodium mordenite zeolite were studied in the reaction of NO reduction. The transition metal cations Ag and Fe were introduced by ion exchange method both at room temperature and 60 °C; modifying the order of component deposition in bimetallic systems. These materials were characterized by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), ultraviolet-visible spectroscopy (UV-Vis), X-Ray photoelectron Spectroscopy (XPS) and High-resolution transmission electron microscopy (HR-TEM). The XPS and UV–Vis spectra of bimetallic samples revealed that under certain preparation conditions Ag+ is reduced with the participation of the Fe2+/Fe3+ ions transition and is present in the form of a Ag reduced state in different proportions of Agm clusters and Ag0 NPs, influenced by the cation deposition order. The catalytic results in the NO reduction reaction using C3H6/CO under an oxidizing atmosphere show also that the order of exchange of Ag and Fe cations in mordenite has a strong effect on catalytic active sites for the reduction of NO.

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HIGHLY ACTIVE AND REUSABLE RHODIUM CATALYST FOR SELECTIVE HYDROGENATION OF NITRILE–BUTADIENE RUBBER

Rubber Chemistry and Technology ◽

10.5254/rct.15.84894 ◽

2015 ◽

Vol 88 (4) ◽

pp. 547-559 ◽

Cited By ~ 2

Author(s):

Peng Cao ◽

Lin Su ◽

Cui Li ◽

Liqun Zhang ◽

Dongmei Yue

Keyword(s):

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Active Sites ◽

Rhodium Catalyst ◽

Infrared Spectrometry ◽

Butadiene Rubber ◽

X Ray ◽

Inductively Coupled ◽

Nitrile Butadiene Rubber ◽

Highly Active

ABSTRACT A recyclable heterogeneous rhodium catalyst (MTS-T-Rh) was prepared by loading Rh species onto an amino-silica support grafted by tannin, an intermediate linker and stabilizer, and fully characterized by X-ray diffraction, infrared spectrometry, scanning electron microscopy, X-ray photoelectron spectroscopy, and inductively coupled plasma. The importance of tannin in improving the activity and stability of the heterogeneous catalyst is discussed. Tannin is a stabilizer for chelating with the Rh-active sites through a chemical bond, which enhances interactions between the Rh nanoparticles and silica. The catalytic hydrogenation of nitrile–butadiene rubber was evaluated in solution. Above 96% conversion and 100% selectivity, the carbon–carbon double bond was obtained at 120 °C and 3.0 MPa H2 after 8 h over MTS-T-Rh. Compared with Rh/SiO2, the as-prepared MTS-T-Rh catalyst exhibited considerably improved reusability, which suffered about 11% deactivation for hydrogenation of nitrile–butadiene rubber, whereas Rh/SiO2 was 53%.

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Lead acid battery recycling for the twenty-first century

Royal Society Open Science ◽

10.1098/rsos.171368 ◽

2018 ◽

Vol 5 (5) ◽

pp. 171368 ◽

Cited By ~ 18

Author(s):

Andrew D. Ballantyne ◽

Jason P. Hallett ◽

D. Jason Riley ◽

Nilay Shah ◽

David J. Payne

Keyword(s):

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Optical Emission ◽

Molar Ratio ◽

Emission Spectrometry ◽

Inductively Coupled ◽

Lead Recovery ◽

Lead Acid

There is a growing need to develop novel processes to recover lead from end-of-life lead-acid batteries, due to increasing energy costs of pyrometallurgical lead recovery, the resulting CO 2 emissions and the catastrophic health implications of lead exposure from lead-to-air emissions. To address these issues, we are developing an iono-metallurgical process, aiming to displace the pyrometallurgical process that has dominated lead production for millennia. The proposed process involves the dissolution of Pb salts into the deep eutectic solvent (DES) Ethaline 200, a liquid formed when a 1 : 2 molar ratio of choline chloride and ethylene glycol are mixed together. Once dissolved, the Pb can be recovered through electrodeposition and the liquid can then be recycled for further Pb recycling. Firstly, DESs are being used to dissolve the lead compounds (PbCO 3 , PbO, PbO 2 and PbSO 4 ) involved and their solubilities measured by inductively coupled plasma optical emission spectrometry (ICP-OES). The resulting Pb 2+ species are then reduced and electrodeposited as elemental lead at the cathode of an electrochemical cell; cyclic voltammetry and chronoamperometry are being used to determine the electrodeposition behaviour and mechanism. The electrodeposited films were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). We discuss the implications and opportunities of such processes.

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Gram-Scale Synthesis of Pt-Cu Nanowires with Enhanced Electrocatalytic Activity towards Methanol Oxidation Reaction

Journal of Nanomaterials ◽

10.1155/2019/1094308 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Ning Sui ◽

Hongxu Gao ◽

Yukai Wang ◽

Jiali Li ◽

Shiyu Qu ◽

...

Keyword(s):

Methanol Oxidation ◽

Photoelectron Spectroscopy ◽

Electrocatalytic Activity ◽

Inductively Coupled Plasma ◽

Active Sites ◽

Structural Defects ◽

Methanol Oxidation Reaction ◽

X Ray ◽

Cu Nanowires ◽

Inductively Coupled

A facile method to prepare Pt-Cu nanowires (NWs) was introduced. Structural characterization such as high-resolution transmission electron microscope (HR-TEM), selected-area electron diffraction (SAED), EDS element mapping, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and inductively coupled plasma mass spectrometry (ICP-MS) showed the formation of Pt-Cu alloy, with a width of 4.5 nm on average. The formation process of Pt-Cu NWs was studied; it was found that bromine ion, who has preferential adsorption on Pt (100) face, served as a growth-directing agent; Brij58 not only served as a protector but also played an important role in forming Pt-Cu NWs; the mechanism was proposed. Their electrocatalytic activity towards methanol oxidation was investigated; we found that the current density of Pt-Cu NWs was 295 mA·mg-1 when the ratio of Pt/Cu is 1 : 1, which is 11.5 and 2.35 times higher than that of pure Pt (26 mA·mg-1) and commercial Pt/C (126 mA·mg-1). The high electrocatalytic activity is attributed to the presence of abundant structural defects and surface active sites on the synthesized Pt-Cu NWs.

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Development of Cu-Modified PVC and PU for Catalytic Generation of Nitric Oxide

Colloids and Interfaces ◽

10.3390/colloids3010033 ◽

2019 ◽

Vol 3 (1) ◽

pp. 33 ◽

Cited By ~ 1

Author(s):

Liana Azizova ◽

Santanu Ray ◽

Sergey Mikhalovsky ◽

Lyuba Mikhalovska

Keyword(s):

Nitric Oxide ◽

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Present Report ◽

Polymer Surface ◽

Optical Emission ◽

Emission Spectrometry ◽

Physiological Level ◽

Inductively Coupled ◽

The Fourier Transform

Nitric oxide (NO) generating surfaces are potentially promising for improving haemocompatibility of blood-contacting biomaterials. In the present report, Cu-modified poly(vinyl chloride) (PVC) and polyurethane (PU) were prepared via polydopamine (pDA)-assisted chelation. The copper content on the PVC and PU modified surfaces, assessed by inductively coupled plasma - optical emission spectrometry (ICP-OES), were about 3.86 and 6.04 nmol·cm−2, respectively. The Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) data suggest that copper is attached to the polymer surface through complex formation with pDA. The cumulative leaching of copper from modified PVC and PU during the five day incubation in phosphate buffered saline (PBS), measured by inductively coupled plasma mass spectrometry (ICP-MS), was about 50.7 ppb and 48 ppb, respectively which is within its physiological level. Modified polymers were tested for their ability to catalytically generate NO by decomposing of endogenous S-nitrosothiol (GSNO). The obtained data show that Cu-modified PVC and PU exhibited the capacity to generate physiological levels of NO which could be a foundation for developing new biocompatible materials with NO-based therapeutics.

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Revealing the reactivity of the Iridium trioxide intermediate for the oxygen evolution reaction in acidic media

10.26434/chemrxiv.8040380.v1 ◽

2019 ◽

Author(s):

Paul Pearce ◽

Chunzhen Yang ◽

Antonella Iadecola ◽

Juan Rodriguez-Carvajal ◽

Gwenaëlle Rousse ◽

...

Keyword(s):

Oxygen Evolution ◽

Photoelectron Spectroscopy ◽

Oxygen Evolution Reaction ◽

Inductively Coupled Plasma ◽

Optical Emission ◽

Charge Compensation ◽

Acidic Media ◽

X Ray ◽

Inductively Coupled ◽

Reaction With Water

We report a strategy to isolate IrO3 as an intermediate for the oxygen evolution reaction (OER). Its reactivity is studied using X-ray absorption spectroscopy, X-ray and neutron diffraction and X-ray photoelectron spectroscopy. Its stability is assessed by using on-line mass spectroscopy and inductively coupled plasma optical emission spectroscopy and presented herein. Upon reaction with water in acidic conditions, we could observe the formation of a new protonated iridate phase of composition H2IrO3. Coupling OER measurements and dissolution rate determination, we could show that its activity and stability are governed by a yet ill-described charge compensation mechanism enlisting reversible bulk proton insertion inside the catalyst structure. This singular property enables an enhanced activity and stability towards dissolution compared to the stellar IrOx/SrIrO3 catalyst. Such a finding opens the route towards the design of new OER catalysts enlisting proton insertion that could be competitive for water splitting in acidic media.

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Rhodium Nanoparticles Stabilized by PEG-Tagged Imidazolium Salts as Recyclable Catalysts for the Hydrosilylation of Internal Alkynes and the Reduction of Nitroarenes

Catalysts ◽

10.3390/catal10101195 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1195

Author(s):

Guillem Fernández ◽

Roser Pleixats

Keyword(s):

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Optical Emission ◽

Water Soluble ◽

X Ray ◽

Rhodium Nanoparticles ◽

Inductively Coupled ◽

Transmission Electron ◽

Internal Alkynes ◽

Recyclable Catalysts

PEGylated imidazolium (bromide and tetrafluoroborate) and tris-imidazolium (bromide) salts containing triazole linkers have been used as stabilizers for the preparation of water-soluble rhodium(0) nanoparticles by reduction of rhodium trichloride with sodium borohydride in water at room temperature. The nanomaterials have been characterized (Transmission Electron Microscopy, Electron Diffraction, X-ray Photoelectron Spectroscopy, Inductively Coupled Plasma-Optical Emission Spectroscopy). They proved to be efficient and recyclable catalysts for the stereoselective hydrosilylation of internal alkynes, in the presence or absence of solvent, and in the reduction of nitroarenes to anilines with ammonia-borane as hydrogen donor in aqueous medium (1:4 tetrahydrofuran/water).

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Investigation of the Repassivation Process of CoCrMo in Simulated Biological Fluids

CORROSION ◽

10.5006/3423 ◽

2020 ◽

Vol 76 (6) ◽

pp. 539-552

Author(s):

Blake Thornley ◽

Robert Beadling ◽

Michael Bryant ◽

Anne Neville

Keyword(s):

Photoelectron Spectroscopy ◽

Active Sites ◽

Biological Fluids ◽

Electrochemical Techniques ◽

Reduction Reaction ◽

Bulk Solution ◽

Molybdenum Oxides ◽

Inductively Coupled ◽

The Reformation ◽

Phosphate Buffered Saline

A thorough investigation into the repassivation process of CoCrMo in multiple simulated biological environments has been undertaken, looking in detail at both the kinetics and composition of the reformed oxide film. Specific focus of this research was aimed at determining the effect of bovine serum albumin (BSA) on these features. The kinetics of repassivation were obtained by using a variety of electrochemical techniques. The current transients formed were fitted to a second-order decay curve, which accouts for two separate phases: coverage and growth. The reformation of the passive film was fastest in a phosphate buffered saline environment, with the presence of BSA delaying this process because it inhibits the oxygen-reduction reaction as it obstructs the active sites of the alloy when adsorbed onto the surface. The composition of the newly formed film was analyzed with x-ray photoelectron spectroscopy. As expected, the film was primarily composed of chromium (III) oxide with small contributions from cobalt and molybdenum oxides. In the presence of BSA, the quantity of molybdenum within the film was drastically reduced; it was shown to be extracted into the bulk solution via inductively coupled mass spectroscopy. This is observed because BSA is able to complex preferentially to the molybdenum ions when the alloy is exposed, extracting them into solution and altering the composition and integrity of the film.

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SYNTHESIS AND CHARACTERIZATION OF TERNARY AL-C-N COMPOUND

International Journal of Modern Physics B ◽

10.1142/s0217979202010993 ◽

2002 ◽

Vol 16 (06n07) ◽

pp. 1132-1137 ◽

Cited By ~ 9

Author(s):

N. JIANG ◽

S. XU ◽

K. N. OSTRIKOV ◽

E. L. TSAKADZE ◽

J. D. LONG ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Optical Emission ◽

Flow Rate Ratio ◽

In Situ Observation ◽

X Ray Diffraction ◽

X Ray ◽

Inductively Coupled

An attempt for modification of carbon nitride material by introduction of Al to form a ternary Al-C-N compound in a thin film deposited using inductively coupled plasma (ICP) assisted DC magnetron sputtering is reported. Optical emission spectroscopy (OES) is used for in-situ observation and identification of reactive species. The films were characterized using x-ray photoelectron spectroscopy (XPS) and x-ray diffraction spectroscopy (XRD). The results indicate that C-N bond is formed in the plasma. The XPS narrow scam spectra confirm the existence of C-Al, sp2C-N and sp3C-N bonds. Elemental proportion of carbon increases with the CH4/N2 flow rate ratio, and has a tendency to saturate. The film is dominated by c-AlN (111), mixed with Al4C3 and AlCN ternary compound.

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Surfactant-assisted microwave synthesis of carbon supported MnO2 nanocomposites and their application for electrochemical supercapacitors

Chemija ◽

10.6001/chemija.v31i1.4168 ◽

2020 ◽

Vol 31 (1) ◽

Author(s):

Jolita Jablonskienė ◽

Dijana Šimkūnaitė ◽

Jūratė Vaičiūnienė ◽

Algirdas Selskis ◽

Audrius Drabavičius ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Optical Emission ◽

High Specific Capacitance ◽

Mass Loading ◽

X Ray ◽

Inductively Coupled ◽

Transmission Electron ◽

Scan Rate

MnO2/C nanocomposites have been prepared using a simple onestep microwave heating method by applying different concentrations of cationic surfactant – cetyl trimethylammonium bromide (CTAB). The morphology and composition of the prepared MnO2/C nanocomposites have been investigated using X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and inductively coupled plasma optical emission spectroscopy (ICP-OES). The electrochemical performance of the prepared nanocomposites has been analysed using cyclic voltammetry. It was found that a high specific capacitance (Cs) of 742 F g−1 at a scan rate of 10 mV s−1 in a 1 M Na2SO4 solution has been obtained for the MnO2/C nanocomposite that has the mass loading of 0.140 mg cm−2 and has been synthesized in the absence of CTAB. Meanwhile, the application of CTAB allowed the increase in the mass loading of MnO2 in the nanocomposites. In the presence of CTAB, the highest value of 654 F g−1 at a scan rate of 10 mV s−1 has been obtained for MnO2/C that has the mass loading of 0.570 mg cm−2. This result confirmed a good performance of the prepared MnO2/C nanocomposites as the electrode material for supercapacitors.

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