A new nanomagnetic Pd-Co bimetallic alloy as catalyst in the Mizoroki–Heck and Buchwald–Hartwig amination reactions in aqueous media

AbstractA Pd-Co bimetallic alloy encapsulated in melamine-based dendrimer supported on magnetic nanoparticles denoted as γ-Fe2O3@MBD/Pd-Co was synthesized by a facile co-complexation-reduction method and characterized sufficiently. The catalytic evaluation of γ-Fe2O3@MBD/Pd-Co showed promising results in the Mizoroki–Heck and Buchwald–Hartwig amination reactions of various iodo-, bromo- and challenging chloroarenes in aqueous media. The synergetic cooperative effect of both Pd and Co and dispersion of the catalyst in water due to the encapsulation of γ-Fe2O3 by melamine-based dendrimer lead to high catalytic performance compared with the monometallic counterparts. The dispersion of the magnetic catalyst also facilitates the recovery and reuse of the catalyst by ten consecutive extraction and final magnetic isolation with no loss of catalytic activity, keeping its structure unaltered.

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A New Nanomagnetic Pd-Co Bimetallic Alloy as Catalyst in the Mizoroki-Heck and Buchwald–Hartwig Amination Reactions in Aqueous Media

10.21203/rs.3.rs-493052/v1 ◽

2021 ◽

Author(s):

Sara Sobhani ◽

Hamed Zarei ◽

José Miguel Sansano

Keyword(s):

Catalytic Activity ◽

Reduction Method ◽

Bimetallic Catalyst ◽

Aqueous Media ◽

Catalytic Performance ◽

Cooperative Effect ◽

Coupling Reactions ◽

Heck Coupling ◽

Bimetallic Alloy ◽

Amination Reaction

Abstract A Pd-Co bimetallic alloy encapsulated in melamine-based dendrimer supported on magnetic nanoparticles denoted as γ-Fe2O3@MBD/Pd-Co was synthesized by a facile co-complexation-reduction method and characterized sufficiently. The catalytic evaluation of γ-Fe2O3@MBD/Pd-Co showed promising results in the Mizoroki-Heck and Buchwald-Hartwig amination reactions of various iodo-, bromo- and challenging chloroarenes in aqueous media. The synergetic cooperative effect of both Pd and Co and dispersion of the catalyst in water due to the encapsulation of γ-Fe2O3 by melamine-based dendrimer lead to high catalytic performance compared with the monometallic counterparts. The dispersion of the magnetic catalyst also facilitates the recovery and reuse of the catalyst by ten consecutive extraction and final magnetic isolation with no loss of catalytic activity, keeping its structure unaltered. Remarkably, this is the first paper on the use of palladium-cobalt bimetallic catalyst for Buchwald-Hartwig amination reaction and the first magnetically recyclable Pd/Co bimetallic catalyst in the Mizoroki-Heck coupling reactions.

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Magnetic Nanoparticles Supported Acidic Ionic Liquid as a Highly Active and Reusable Catalyst for Esterification

Materials Science Forum ◽

10.4028/www.scientific.net/msf.852.485 ◽

2016 ◽

Vol 852 ◽

pp. 485-488 ◽

Cited By ~ 1

Author(s):

Qiang Zhang ◽

Xin Zhao ◽

Xue Hua Zhu ◽

Ji Hang Li

Keyword(s):

Ionic Liquid ◽

Catalytic Activity ◽

Magnetic Nanoparticles ◽

Catalytic Performance ◽

Significant Loss ◽

Reusable Catalyst ◽

Hydrogen Sulfate ◽

External Magnet ◽

Acidic Ionic Liquid ◽

Highly Active

A magnetic nanoparticles supported dual acidic ionic liquid catalyst was prepared via anchoring 3-sulfobutyl-1-(3-propyltriethoxysilane) imidazolium hydrogen sulfate onto the surface of silica-coated Fe3O4 nanoparticles. And this novel supported acidic ionic liquid catalyst showed good catalytic performance in esterification. More importantly, the catalyst could be easily recovered by an external magnet and reused six times without significant loss of catalytic activity.

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Electro-Catalytic Performance of Different Pt/Ag Ratio on H2O2 Electro-Reduction for Direct NaBH4-H2O2 Fuel Cell

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.986-987.59 ◽

2014 ◽

Vol 986-987 ◽

pp. 59-62

Author(s):

Ting Fang Yang ◽

Dan Zheng ◽

Zao Xi Yu

Keyword(s):

Cyclic Voltammetry ◽

Catalytic Activity ◽

Reduction Method ◽

Catalytic Performance ◽

Performance Tests ◽

Peak Current Density ◽

Acid Media ◽

Electro Catalytic Activity ◽

Xrd And Tem ◽

Better Than

In this paper the different proportional Pt/Ag on XC-72 carbon are studied to serve as the electro-catalysts of H2O2in acid media. All catalysts are prepared by impregnation reduction method and characterized by XRD and TEM. The electrochemical performance tests are examined by cyclic voltammetry (CV) at 25°C and 30°C, respectively. The results suggest that the peak current density increases with increasing the Ag content in Pt-Ag/C. Attributed to the temperature factor, the electro-catalytic activity of all catalysts at 30°C is better than that of 25°C.

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Bio-assisted synthesized Ag(0) nanoparticles stabilized on hybrid of sepiolite and chitin: efficient catalytic system for xanthene synthesis

Scientific Reports ◽

10.1038/s41598-020-71866-2 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Fatemeh Ghoreyshi Kahangi ◽

Morteza Mehrdad ◽

Majid M. Heravi ◽

Samahe Sadjadi

Keyword(s):

Silver Nanoparticles ◽

Catalytic Activity ◽

Specific Surface ◽

Catalytic System ◽

Synergistic Effects ◽

Aqueous Media ◽

Catalytic Performance ◽

High Catalytic Activity ◽

Mean Diameter ◽

High Yields

Abstract In this work, with the use of two natural compounds, chitin and sepiolite clay, a novel covalent hybrid is fabricated and applied as a support for the stabilization of silver nanoparticles with the aid of Kombucha extract as a natural reducing agent. The resultant catalytic system, Ag@Sep-N–CH, was characterized via XRD, TEM, FTIR, ICP, SEM, TGA, UV–Vis and BET. It was found that fine Ag(0) nanoparticles with mean diameter of 6.1 ± 1.8 nm were formed on the support and the specific surface area of the catalyst was 130 m2 g−1. The study of the catalytic performance of Ag@Sep-N–CH for catalyzing synthesis of xanthenes in aqueous media under mild reaction condition confirmed that Ag@Sep-N–CH exhibited high catalytic activity and could promote the reaction of various substrates to furnish the corresponding products in high yields. Moreover, the contribution of both chitin and sepiolite to the catalysis has been affirmed. It was found that hybridization of these two components led to synergistic effects and consequently improved the observed catalytic activity. Notably, the catalyst was recyclable up to several reaction runs.

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The design and catalytic performance of molybdenum active sites on an MCM-41 framework for the aerobic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran

Catalysis Science & Technology ◽

10.1039/c8cy02291g ◽

2019 ◽

Vol 9 (3) ◽

pp. 811-821 ◽

Cited By ~ 7

Author(s):

Zhao-Meng Wang ◽

Li-Juan Liu ◽

Bo Xiang ◽

Yue Wang ◽

Ya-Jing Lyu ◽

...

Keyword(s):

Catalytic Activity ◽

Active Sites ◽

Aerobic Oxidation ◽

Catalytic Performance ◽

Mcm 41

The catalytic activity decreases as –(SiO)3Mo(OH)(O) > –(SiO)2Mo(O)2 > –(O)4–MoO.

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Catalytic Performance of Imidazolide Basic Ionic Liquid in Knoevenagel Reactions in Aqueous Media

CHINESE JOURNAL OF CATALYSIS (CHINESE VERSION) ◽

10.3724/sp.j.1088.2011.01238 ◽

2011 ◽

Vol 32 (4) ◽

pp. 693-698

Author(s):

Xuewei CHEN ◽

Hongbing SONG ◽

Xuehui LI ◽

Furong WANG ◽

Yu QIAN

Keyword(s):

Ionic Liquid ◽

Aqueous Media ◽

Catalytic Performance ◽

Basic Ionic Liquid

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Influence of the Reduction Temperature and the Nature of the Support on the Performance of Zirconia and Alumina-Supported Pt Catalysts for n-Dodecane Hydroisomerization

Catalysts ◽

10.3390/catal11010088 ◽

2021 ◽

Vol 11 (1) ◽

pp. 88

Author(s):

Diana García-Pérez ◽

Maria Consuelo Alvarez-Galvan ◽

Jose M. Campos-Martin ◽

Jose L. G. Fierro

Keyword(s):

Catalytic Activity ◽

Surface Area ◽

Catalytic Properties ◽

Catalytic Performance ◽

Major Influence ◽

Pt Catalysts ◽

Reduction Temperature ◽

Metal Dispersion ◽

Tungsten Oxides ◽

Supported Pt Catalysts

Catalysts based on zirconia- and alumina-supported tungsten oxides (15 wt % W) with a small loading of platinum (0.3 wt % Pt) were selected to study the influence of the reduction temperature and the nature of the support on the hydroisomerization of n-dodecane. The reduction temperature has a major influence on metal dispersion, which impacts the catalytic activity. In addition, alumina and zirconia supports show different catalytic properties (mainly acid site strength and surface area), which play an important role in the conversion. The NH3-TPD profiles indicate that the acidity in alumina-based catalysts is clearly higher than that in their zirconia counterparts; this acidity can be attributed to a stronger interaction of the WOx species with alumina. The PtW/Al catalyst was found to exhibit the best catalytic performance for the hydroisomerization of n-dodecane based on its higher acidity, which was ascribed to its larger surface area relative to that of its zirconia counterparts. The selectivity for different hydrocarbons (C7–10, C11 and i-C12) was very similar for all the catalysts studied, with branched C12 hydrocarbons being the main products obtained (~80%). The temperature of 350 °C was clearly the best reduction temperature for all the catalysts studied in a trickled-bed-mode reactor.

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High-throughput computational-experimental screening protocol for the discovery of bimetallic catalysts

npj Computational Materials ◽

10.1038/s41524-021-00605-6 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Byung Chul Yeo ◽

Hyunji Nam ◽

Hyobin Nam ◽

Min-Cheol Kim ◽

Hong Woo Lee ◽

...

Keyword(s):

High Throughput ◽

Bimetallic Catalysts ◽

High Throughput Screening ◽

Direct Synthesis ◽

Catalytic Performance ◽

Platinum Group Metals ◽

Pt Catalyst ◽

Electronic Density ◽

Bimetallic Alloy ◽

Screening Protocol

AbstractTo accelerate the discovery of materials through computations and experiments, a well-established protocol closely bridging these methods is required. We introduce a high-throughput screening protocol for the discovery of bimetallic catalysts that replace palladium (Pd), where the similarities in the electronic density of states patterns were employed as a screening descriptor. Using first-principles calculations, we screened 4350 bimetallic alloy structures and proposed eight candidates expected to have catalytic performance comparable to that of Pd. Our experiments demonstrate that four bimetallic catalysts indeed exhibit catalytic properties comparable to those of Pd. Moreover, we discover a bimetallic (Ni-Pt) catalyst that has not yet been reported for H2O2 direct synthesis. In particular, Ni61Pt39 outperforms the prototypical Pd catalyst for the chemical reaction and exhibits a 9.5-fold enhancement in cost-normalized productivity. This protocol provides an opportunity for the catalyst discovery for the replacement or reduction in the use of the platinum-group metals.

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A diffusion anisotropy descriptor links morphology effects of H-ZSM-5 zeolites to their catalytic cracking performance

Communications Chemistry ◽

10.1038/s42004-021-00543-w ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Xiaoliang Liu ◽

Jing Shi ◽

Guang Yang ◽

Jian Zhou ◽

Chuanming Wang ◽

...

Keyword(s):

Catalytic Activity ◽

Catalytic Cracking ◽

Catalytic Performance ◽

Zeolite Catalysts ◽

Time Resolved ◽

Cracking Performance ◽

Morphology Effect ◽

Ft Ir ◽

The Difference ◽

Dynamics Simulations

AbstractZeolite morphology is crucial in determining their catalytic activity, selectivity and stability, but quantitative descriptors of such a morphology effect are challenging to define. Here we introduce a descriptor that accounts for the morphology effect in the catalytic performances of H-ZSM-5 zeolite for C4 olefin catalytic cracking. A series of H-ZSM-5 zeolites with similar sheet-like morphology but different c-axis lengths were synthesized. We found that the catalytic activity and stability is improved in samples with longer c-axis. Combining time-resolved in-situ FT-IR spectroscopy with molecular dynamics simulations, we show that the difference in catalytic performance can be attributed to the anisotropy of the intracrystalline diffusive propensity of the olefins in different channels. Our descriptor offers mechanistic insight for the design of highly effective zeolite catalysts for olefin cracking.

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Performance Analysis of TiO2-Modified Co/MgAl2O4 Catalyst for Dry Reforming of Methane in a Fixed Bed Reactor for Syngas (H2, CO) Production

Energies ◽

10.3390/en14113347 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3347

Author(s):

Arslan Mazhar ◽

Asif Hussain Khoja ◽

Abul Kalam Azad ◽

Faisal Mushtaq ◽

Salman Raza Naqvi ◽

...

Keyword(s):

Catalytic Activity ◽

Fixed Bed ◽

Catalytic Performance ◽

Dry Reforming ◽

Fixed Bed Reactor ◽

Dry Reforming Of Methane ◽

Catalyst Stability ◽

Feed Ratio ◽

Catalyst Loading ◽

Impregnation Method

Co/TiO2–MgAl2O4 was investigated in a fixed bed reactor for the dry reforming of methane (DRM) process. Co/TiO2–MgAl2O4 was prepared by modified co-precipitation, followed by the hydrothermal method. The active metal Co was loaded via the wetness impregnation method. The prepared catalyst was characterized by XRD, SEM, TGA, and FTIR. The performance of Co/TiO2–MgAl2O4 for the DRM process was investigated in a reactor with a temperature of 750 °C, a feed ratio (CO2/CH4) of 1, a catalyst loading of 0.5 g, and a feed flow rate of 20 mL min−1. The effect of support interaction with metal and the composite were studied for catalytic activity, the composite showing significantly improved results. Moreover, among the tested Co loadings, 5 wt% Co over the TiO2–MgAl2O4 composite shows the best catalytic performance. The 5%Co/TiO2–MgAl2O4 improved the CH4 and CO2 conversion by up to 70% and 80%, respectively, while the selectivity of H2 and CO improved to 43% and 46.5%, respectively. The achieved H2/CO ratio of 0.9 was due to the excess amount of CO produced because of the higher conversion rate of CO2 and the surface carbon reaction with oxygen species. Furthermore, in a time on stream (TOS) test, the catalyst exhibited 75 h of stability with significant catalytic activity. Catalyst potential lies in catalyst stability and performance results, thus encouraging the further investigation and use of the catalyst for the long-run DRM process.

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