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palladium
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Catalyst-Free and Green Synthesis of Some Novel Benzamide Derivatives
, Article Journal of Heterocyclic Chemistry ; Volume 52, Issue 6 , November , 2015 , Pages 1848-1857 ; 0022152X (ISSN) ; Rostami, M ; Mirkhani, V ; Moghadam, M ; Mohammadpoor Baltork, I ; Tangestaninejad, S ; Jamali Moghadam, A ; Kia, R ; Sharif University of Technology
HeteroCorporation
2015
Abstract
In the present work, a simple, green, rapid, and catalyst-free procedure for the synthesis of benzamide derivatives by ring opening of azlactones with diamines such as ethylene diamine and 1,3-propylenediamine is described. The present method offers several advantages such as short reaction times, easy work-up, and mild reaction conditions in the absence of catalyst and any toxic solvent and material. In addition, the structure obtained by X-ray crystallography was compared with the theoretical results obtained by density functional theory using the B3LYP functional and cc-pVDZ basis sets
Fabrication and characterization and biosensor application of gold nanoparticles on the carbon nanotubes
, Article Applied Surface Science ; Volume 355 , November , 2015 , Pages 1175-1179 ; 01694332 (ISSN) ; Aghababaie, N ; Mobasheri, H ; Zand Salimi, K ; Akbarzadeh Pasha, M ; Vesaghi, M. A ; Sharif University of Technology
Elsevier
2015
Abstract
Gold nanoparticles (Au NPs) were synthesized by co-deposition of RF-sputtering and RF-PECVD from acetylene gas and Au target on the carbon nanotubes (CNTs). The CNTs were prepared by thermal chemical vapor deposition (TCVD) and Pd nanoparticles catalyst. TEM image shows that high-density and uniform distribution of Au NPs were grown on the CNTs. XRD analysis indicates that Au NPs have fcc crystal structure and CNTs have a good graphite structure. Raman spectroscopy results suggest that our sample includes double-walled CNTs. It is resulted that intensity of D-band reduces and G-band intensity raises and radial breathing mode (RBM) is changed by immobilizing of Au NPs on the CNTs. Raman...
Observation of a crossover in kinetic aggregation of Palladium colloids
, Article Applied Surface Science ; Volume 353 , 2015 , Pages 1143-1149 ; 01694332 (ISSN) ; Ranjbar, M ; Rouhani, S ; Sharif University of Technology
Elsevier
2015
Abstract
We use field emission scanning electron microscope (FE-SEM) to investigate the growth of palladium colloids over the surface of thin films of WO3 /glass. The film is prepared by Pulsed Laser Deposition (PLD) at different temperatures. A PdCl2 (aq) droplet is injected on the surface and in the presence of steam hydrogen the droplet is dried through a reduction reaction process. Two distinct aggregation regimes of palladium colloids are observed over the substrates. We argue that the change in aggregation dynamics emerges when the measured water drop Contact Angel (CA) for the WO3 /glass thin films passes a certain threshold value, namely CA ≈ 46°, where a...
Effects of functionalization and catalyst treatments on selective behavior of multi-walled carbon nanotube-supported palladium catalysts in hydrogenation of acetylene
, Article Research on Chemical Intermediates ; Volume 41, Issue 2 , 2015 , Pages 1023-1034 ; 09226168 (ISSN) ; Kazemeini, M ; Rashidi, A. M ; Sharif University of Technology
Kluwer Academic Publishers
2015
Abstract
Two nanocatalysts of palladium over multi-walled carbon nanotubes (MWCNT) were synthesized and their catalytic properties evaluated in selective hydrogenation of acetylene. Different procedures were applied to synthesize catalysts which resulted in two distinct average particle sizes of palladium (Pd) over the MWCNT. The resulting catalysts displayed dissimilar NH3-TPD behaviors as well as different selectivity performances at lower temperatures. While enhancement of the hydrogen transfer mechanism occurred upon the temperature increase, similar behaviors for the aforementioned materials were obtained. Furthermore, it was revealed that the catalytic performance at higher temperatures did not...
Hydrogen sensing properties of multi-walled carbon nanotube films sputtered by Pd
, Article International Journal of Hydrogen Energy ; Volume 35, Issue 9 , 2010 , Pages 4445-4449 ; 03603199 (ISSN) ; Mortazavi, S. Z ; Iraji zad, A ; Rahimi, F ; Sharif University of Technology
Abstract
Multi-Walled Carbon nanotube (MWCNTs) films were obtained by Thermal Chemical Vapor Deposition method and coated by palladium sputtering process. Raman spectroscopy was used to study alteration in quality of the carbon nanotubes after the sputtering process. Fourier Transform Infra Red (FTIR) spectroscopy showed that hydrogenation process can reduce the C{double bond, long}O to C-O and also produce O-H bond. Furthermore, the electrical resistance measurement for Pd/MWNTs films was performed in a chamber with 1% hydrogen gas in a constant dry air flow. Hydrogen sensing behavior of the films was investigated at 50 °C. Pd/MWCNTs films presented an irreversible gas response to hydrogen in the...
Control design and passivity analysis for scaled one-dimensional bilateral teleoperated nanomanipulation
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings, 13 November 2009 through 19 November 2009 ; Volume 10, Issue PART A , 2010 , Pages 279-285 ; 9780791843833 (ISBN) ; Vossoughi, G. R ; Ahmadian, M. T ; Tajaddodianfar, F ; Sharif University of Technology
Abstract
In this paper, a novel control approach for onedimensional bilateral teleoperated nanomanipulation system is proposed. While manipulating objects with a nanomanipulator, real time visual feedback is not available. So, force feedback is used to compensate for the lack of visual information. Since nanometer scale forces are dominated by surface forces instead of inertial forces as in macro world, scaling of nanoforces is one of the major issues of teleoperation system. The Hertz elastic contact model is used to model the interactions between the slave robot and the environment. The proposed approach uses the simple proportional derivative control, i.e., the master and slave robots are...
Electroless plating of palladium on WO3 films for gasochromic applications
, Article Solar Energy Materials and Solar Cells ; Volume 94, Issue 2 , 2010 , Pages 201-206 ; 09270248 (ISSN) ; Tahmasebi Garavand, N ; Mahdavi, S. M ; Iraji Zad, A ; Sharif University of Technology
2010
Abstract
Nowadays, gasochromic Pd/WO3 coatings as optically switchable materials during H2 absorption have become more interesting due to their novel applications in smart windows and gas sensor devices. In this study, WO3 films were fabricated by Pulsed Laser Deposition (PLD) on glass substrates. Using an electroless method, Pd nanoparticles were deposited on the surface of the produced films. The effect of Pd growth time on coloring/bleaching rate was studied for different submerging times (1, 2, 5, 10, 15, 20 and 40 min). The best coloring/bleaching velocity was attained with a growth time of 2 min. The effect of growing time and growth feature of Pd particles was further studied using Scanning...
Au-Pd bimetallic nanoparticle electrodes for direct electroreduction of hexavalent chromium complexes
, Article Australian Journal of Chemistry ; Volume 69, Issue 4 , 2016 , Pages 423-430 ; 00049425 (ISSN) ; Hariri, M. B ; Kushwaha, A ; Dolati, A ; Ghorbani, M ; Goh, G. K. L ; Sharif University of Technology
CSIRO
2016
Abstract
This paper reports a simple, low-cost, and effective electrochemical technique for sensing and reducing CrVI based on a Au-Pd bimetallic nanoparticle (BNP)-decorated indium tin oxide (ITO) conducting glass electrode. It was observed that the Au-Pd BNP-decorated ITO electrode could significantly boost the electrochemical reduction of CrVI when compared with either Au nanoparticle- or Pd nanoparticle-decorated ITO electrodes. These BNP-decorated electrodes exhibited a wide linear concentration range of 0.001-100 μM, a very low detection limit (signal-to-noise ratio = 3) of 0.3 nM, and a high sensitivity of 1.701 μA μM-1. From electrochemical impedance spectroscopy, it was revealed that this...
Hydrogenation of crude terephthalic acid by supported Pd and Pd-Sn catalysts on functionalized multiwall carbon nanotubes
, Article Chemical Engineering Research and Design ; Volume 109 , 2016 , Pages 41-52 ; 02638762 (ISSN) ; Safekordi, A. A ; Rashidzadeh, M ; Rashidi, A. M ; Khorasheh, F ; Sharif University of Technology
Institution of Chemical Engineers
2016
Abstract
Liquid phase hydro-purification of crude terephthalic acid (CTA) was performed using supported Pd and Pd-Sn catalysts on functionalized multi-wall carbon nanotubes (FMWCNT). Pd/FMWCNT catalysts were prepared by wet impregnation with Pd loadings of 0.05 to 0.6 wt.%. Pd-Sn/FMWCNT catalysts were prepared by co-impregnation (CI) and successive impregnation (SI) using 0.3 wt.% Pd loading and Sn/Pd molar ratios of 0.1 and 0.35 for the CI method and 0.05 to 0.35 for the SI method. Pd loading of 0.3 wt.% for Pd/FMWCNT was sufficient to decrease the 4-carboxybenzaldehyde (4-CBA) content of CTA from 2100 ppm to 5.5 ppm without excessive hydrogenation of terephthalic acid (TA). The commercial catalyst...
Monodentate palladium(0)-[60]fullerene complexes of diphosphine ligands as efficient and sustainable nanocatalysts for the Mizoroki-Heck coupling reaction of aryl chlorides
, Article New Journal of Chemistry ; Volume 41, Issue 18 , 2017 , Pages 9701-9709 ; 11440546 (ISSN) ; Hosseinzadeh, M ; Zarepour Jevinani, M ; Ghanbari, B ; Sharif University of Technology
Royal Society of Chemistry
2017
Abstract
Two mononuclear coordination complexes of fullerene[60] with Pd(dba)2 (dba = dibenzylideneacetone), [(η2-C60)Pd(Ph2P(CH2)2PPh2C(H)C(O)R)2] (R = C10H7 (1), C6H4Cl (2)), have been prepared using a simple procedure to explore new directions in palladium catalysis and nanocarbon chemistry. The palladium(0)-[60]fullerene complexes incorporating unsymmetrical phosphorus ylides have been characterized by 1H, 13C and 31P NMR spectroscopic methods and other conventional techniques such as IR, TGA, SEM, ICP-OES, EDX and TEM analysis. Attributed to the enhanced dispersity and uniform size of the Pd nanoparticles with phosphine-functionalized fullerenes, the prepared catalysts exhibited comparable...
On the controllability of phase formation in rapid solidification of high entropy alloys
, Article Journal of Alloys and Compounds ; Volume 748 , 2018 , Pages 679-686 ; 09258388 (ISSN) ; Aitken, Z. H ; Tavakoli, R ; Zhang, Y. W ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The demonstration of high entropy alloys (HEAs), or more generally multi-principal-element alloys (MPEAs), which display a greater resistance to softening at elevated temperatures and embrittlement at cryogenic temperatures, has offered an accessible alternative alloying process for materials scientists and engineers. Although solidification is a fundamental process in synthesis of alloys which strongly affects their microstructure and properties, a firm understanding of this process in HEAs is scarce. Here, using molecular dynamics (MD) simulations, we study the rapid solidification of the multi-principal-element CoFeNiPd alloy as a prototypical single-phase HEA. Our simulations reveal an...
Suzuki–Miyaura coupling reaction in water in the presence of robust palladium immobilized on modified magnetic Fe3O4 nanoparticles as a recoverable catalyst
, Article Applied Organometallic Chemistry ; Volume 32, Issue 2 , 2018 ; 02682605 (ISSN) ; Naimi Jamal, M. R ; Moghaddam, F. M ; Ayati, S. E ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
Aryl halides and especially inactive aryl chlorides were coupled to benzenoid aromatic rings in a Suzuki–Miyaura coupling reaction in the absence of organic solvents and toxic phosphine ligands. The reaction was catalysed by a recoverable magnetic nanocatalyst, Pd@Fe3O4, in aqueous media. This method is green, and the catalyst is easily removed from the reaction media using an external magnetic field and can be re-used at least 10 times without any considerable loss in its activity. The catalyst was characterized using scanning and transmission electron microscopies, thermogravimetric analysis, inductively coupled plasma spectroscopy, Fourier transform infrared spectroscopy, CHN analysis,...
Supported PtxPd1-x bimetallic nanoparticles on ionic liquid-functionalized SiO2@graphene oxide nanocomposite and its application as an effective multiphasic catalyst
, Article Applied Catalysis A: General ; Volume 579 , 2019 , Pages 30-43 ; 0926860X (ISSN) ; Giannakis, S ; Gholami, M. R ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this work, PtxPd1-x (x = 0, 0.5, and 1)nanoparticles (NPs)were synthesized on the surface of SiO2@graphene oxide which covered by 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6)ionic liquid (IL)layer. FT-IR spectroscopy, zeta potential, CHN elemental analysis, XRD, XPS, SEM, EDX, TEM, TGA, BET, and ICP-AES techniques were applied for the characterization of the multiphasic catalyst. The as-prepared nanocomposite was used as an effective heterogeneous catalyst for the oxidation of cyclohexene by molecular oxygen, as a green oxidant. Different experimental conditions such as oxygen pressure, reaction time, reaction temperature and amount of catalyst were investigated in this...
Evaluating the optimal digestion method and value distribution of precious metals from different waste printed circuit boards
, Article Journal of Material Cycles and Waste Management ; Volume 22, Issue 5 , 2020 , Pages 1690-1698 ; Yaghmaei, S ; Esmaeili, A ; Sharif University of Technology
Springer
2020
Abstract
Knowing the metal content of electronic waste is essential to evaluate metal recovery. Lack of a standard method for digestion of precious metals from electronic waste has resulted in difficulty in comparison to the efficiency of recovery. In this study, different precious metal digestion methods and economic value of precious metals from different types of waste printed circuit boards in different fraction sizes, including computer printed circuit boards, mobile phone printed circuit boards, television printed circuit boards, fax machine printed circuit boards, copy machine printed circuit boards, and central processing unit were examined. The optimal digestion method using aqua regia,...
Catalytic and antibacterial properties of 3-dentate carboxamide Pd/Pt complexes obtained via a benign route
, Article Applied Organometallic Chemistry ; Volume 34, Issue 4 , April , 2020 ; Bagherzadeh, M ; Meghdadi, S ; Fadaei Tirani, F ; Schenk Joß, K ; Rabiee, N ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
The complexes PdII(qcq)(OAc) and PtII(qcq)Cl have been synthesized using environmentally benign synthesized ligands and characterized by elemental analyses: Fourier transform infrared spectroscopy, UV–visible spectroscopy, 1H NMR spectroscopy, and X-ray diffraction. The catalytic activity of the complex was assessed, in different media, for the Mizoroki–Heck coupling reaction for typical aryl halides and terminal olefins under aerobic conditions. Since the base and the solvent were found to influence the efficiency of the reaction, reaction conditions, temperature, time, and the amount of K3PO4 and a mixture of H2O/PEG, were optimized. We found, for the Mizoroki–Heck reaction coupling less...
Conversion of CO into CO2 by high active and stable PdNi nanoparticles supported on a metal-organic framework
, Article Frontiers of Chemical Science and Engineering ; Volume 16, Issue 7 , 2022 , Pages 1139-1148 ; 20950179 (ISSN) ; Karimi Sabet, J ; Abbasi, Z ; Ghotbi, C ; Sharif University of Technology
Higher Education Press Limited Company
2022
Abstract
The solubility of Pd(NO3)2 in water is moderate whereas it is completely soluble in diluted HNO3 solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH2(Cr) were synthesized by aqueous solution of Pd(NO3)2 and Pd(NO3)2 solution in dilute HNO3 and used for CO oxidation reaction. The catalysts synthesized with Pd(NO3)2 solution in dilute HNO3 showed lower activity. The aqueous solution of Pd(NO3)2 was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd70Ni30/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd + Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution...
Shape-Controlled photochemical synthesis of noble metal nanocrystals based on reduced graphene oxide
, Article ACS Applied Materials and Interfaces ; Volume 14, Issue 14 , 2022 , Pages 16527-16537 ; 19448244 (ISSN) ; Naseri, A ; Li, T ; Ostovan, A ; Asadian, E ; Jia, R ; Shi, L ; Huang, L ; Moshfegh, A. Z ; Sharif University of Technology
American Chemical Society
2022
Abstract
The fabrication of supported noble metal nanocrystals (NCs) with well-controlled morphologies have been attracted considerable interests due to their merits in a wide variety of applications. Photodeposition is a facile and effective method to load metals over semiconductors in a simple slurry reactor under irradiation. By optimizing the photodeposition process, the size, chemical states, and the geometrical distribution of metal NCs have been successfully tuned. However, metal NCs with well-controlled shapes through the photodeposition process have not been reported until now. Here, we report our important advances in the controlled photodeposition process to load regular noble metal NCs....
Synthesis of some new 1,4-distyrylbenzenes using immobilized palladium nanoparticles on silica functionalized morpholine as a recyclable catalyst
, Article Synthesis ; Issue 10 , 2011 , Pages 1609-1615 ; 00397881 (ISSN) ; Gharavi, A ; Nezhad, M. R. H ; Panahi, F ; Sharbati, M. T ; Sharif University of Technology
Abstract
Some new 1,4-distyrylbenzene derivatives were synthesized by using immobilized palladium nanoparticles on silica-bonded N-propyl morpholine (PNP-SBNPM) as a heterogeneous catalyst. These one-pot reactions afforded a range of stereoselective, symmetrical (E)-1,4-distyrylbenzene derivatives with high yields (78-90%). The green catalyst system is recyclable and allows facile product isolation. The recycled catalyst could be reused six times without appreciable loss of catalytic activity
Immersed single-drop microextraction-electrothermal vaporization atomic absorption spectroscopy for the trace determination of mercury in water samples
, Article Journal of Hazardous Materials ; Volume 165, Issue 1-3 , 2009 , Pages 353-358 ; 03043894 (ISSN) ; Naderi, M ; Sharif University of Technology
2009
The decoration of TiO2/reduced graphene oxide by Pd and Pt nanoparticles for hydrogen gas sensing
, Article International Journal of Hydrogen Energy ; Volume 37, Issue 20 , 2012 , Pages 15423-15432 ; 03603199 (ISSN) ; Ghasemi, S ; Irajizad, A ; Akhavan, O ; Gholami, M. R ; Sharif University of Technology
Elsevier
2012
Abstract
Reduced graphene oxide (RGO) was used to improve the hydrogen sensing properties of Pd and Pt-decorated TiO2 nanoparticles by facile production routes. The TiO2 nanoparticles were synthesized by sol-gel method and coupled on GO sheets via a photoreduction process. The Pd or Pt nanoparticles were decorated on the TiO2/RGO hybrid structures by chemical reduction. X-ray photoelectron spectroscopy demonstrated that GO reduction is done by the TiO2 nanoparticles and Ti-C bonds are formed between the TiO2 and the RGO sheets as well. Gas sensing was studied with different concentrations of hydrogen ranging from 100 to 10,000 ppm at various temperatures. High sensitivity (92%) and fast response time...