Heterogeneous copper-catalyzed synthesis of diaryl sulfones

2021 ◽  
Author(s):  
Xinchi Gong ◽  
Zhengqi Shen ◽  
Ganghu Wang ◽  
Lingling Qu ◽  
Chunyin Zhu
Keyword(s):  
Catalytic Activity ◽  
Copper Nanoparticles ◽  
High Catalytic Activity ◽  
First Time

A carbon-supported copper nanoparticles (Cu-NP) with high catalytic activity for the synthesis of diaryl sulfonens is reported. For the first time, this Cu-NP was proved to be able to effectively...

Catalytic activity of palladium-doped silver dilute nanoalloys for formate oxidation from a theoretical perspective

2019 ◽  
Vol 21 (40) ◽  
pp. 22598-22610 ◽  
Author(s):  
Nan Zhang ◽  
Fuyi Chen ◽  
Longfei Guo
Keyword(s):  
Catalytic Activity ◽  
Oxidation Reaction ◽  
Theoretical Perspective ◽  
Single Atom ◽  
High Catalytic Activity ◽  
Formate Oxidation ◽  
First Time ◽  
Single Atom Alloys

We demonstrate for the first time that the Pd1Ag single-atom alloys exhibit a high catalytic activity for formate oxidation reaction.

scholarly journals N,N-Dimethylformamide-stabilized copper nanoparticles as a catalyst precursor for Sonogashira–Hagihara cross coupling

RSC Advances ◽  
2017 ◽  
Vol 7 (37) ◽  
pp. 22869-22874 ◽  
Author(s):  
Hideo Oka ◽  
Katsuya Kitai ◽  
Takeyuki Suzuki ◽  
Yasushi Obora
Keyword(s):  
Catalytic Activity ◽  
Copper Nanoparticles ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
High Catalytic Activity ◽  
Catalyst Precursor ◽  
Cross Coupling Reaction

We found that DMF-stabilized Cu NPs have high catalytic activity in the Sonogashira cross-coupling reaction at low catalyst loadings (0.2 mol%).

Direct Synthesis and Catalytic Reactivity of Highly Ordered Large-Pore Methylaminopropyl-Functionalized SBA-15 Materials

2005 ◽  
Vol 58 (7) ◽  
pp. 507 ◽  
Author(s):  
Xueguang Wang ◽  
Soofin Cheng
Keyword(s):  
Catalytic Activity ◽  
Inorganic Salt ◽  
Direct Synthesis ◽  
Initial Mixture ◽  
Tetraethyl Orthosilicate ◽  
High Catalytic Activity ◽  
Amino Groups ◽  
Large Pore ◽  
Catalytic Reactivity ◽  
First Time

Highly ordered large-pore SBA-15 materials functionalized with a high loading of amino groups were synthesized for the first time by co-condensation of tetraethyl orthosilicate (TEOS) and [3-(methylamino)propyl]trimethoxysilane (MAPTMS) using an amphiphilic block copolymer. Addition of inorganic salt to the initial mixture greatly enhanced the mesostructure ordering and stability of the mesoporous materials. The materials thus obtained showed high catalytic activity and selectivity for the synthesis of flavanones by means of the Claisen–Schmidt condensation in the absence of solvent.

High catalytic activity for water oxidation based on nanostructured nickel phosphide precursors

2015 ◽  
Vol 51 (58) ◽  
pp. 11626-11629 ◽  
Author(s):  
Ali Han ◽  
Huanlin Chen ◽  
Zijun Sun ◽  
Jun Xu ◽  
Pingwu Du
Keyword(s):  
Catalytic Activity ◽  
Noble Metal ◽  
Water Oxidation ◽  
Oxidation Catalysis ◽  
High Catalytic Activity ◽  
Nickel Phosphide ◽  
Catalyst Precursor ◽  
Metal Free ◽  
Water Oxidation Catalysis ◽  
First Time

For the first time, noble-metal-free nickel phosphide (Ni2P) was used as an excellent catalyst precursor for water oxidation catalysis.

scholarly journals Study on Reduction of 4-nitrophenol by Magnetic Maize Straw Supported with Copper Nanoparticles

2021 ◽  
Author(s):  
Yang Yu ◽  
Hong Guo ◽  
Pengyuan Wang ◽  
Shangru Zhai ◽  
Jiazhi Han ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Aqueous Solution ◽  
Catalytic Activity ◽  
Copper Nanoparticles ◽  
Agricultural Waste ◽  
High Catalytic Activity ◽  
Cu Nanoparticles ◽  
Carboxylate Groups ◽  
Maize Straw ◽  
Self Aggregation

Abstract In this work, magnetic maize straw was prepared by the amidation process using renewable maize straw as starting material. After magnetic succinylated maize straw (Mag-S-MS) was mixed with cupric ions aqueous solution, Cu (II) could be captured by the amino and carboxylate groups. Then, the bonded Cu (II) was converted to valuable Cu nanoparticles (Cu NPS). It was characterized by SEM-EDS, XRD, XPS, and TGA, which indicated Cu NPS were formed successfully on Mag-S-MS without self-aggregation and oxidation. The above nanocomposites could be employed as a catalyst for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The effect of the dosage of Cu NPS loaded-Mag-S-MS, the initial concentrations of NaBH4 and 4-NP were investigated, and a possible mechanism was discussed. The catalyst maintained relatively high catalytic activity after five cycle tests. Due to its superparamagnetic nature, it could be quickly collected from the aqueous solution under a magnetic field. These results could provide a method for using agricultural waste in nano catalytic reaction.

Rationally designing mixed Cu–(μ-O)–M (M = Cu, Ag, Zn, Au) centers over zeolite materials with high catalytic activity towards methane activation

2018 ◽  
Vol 20 (41) ◽  
pp. 26522-26531 ◽  
Author(s):  
Guiru Wang ◽  
Ling Huang ◽  
Wei Chen ◽  
Jian Zhou ◽  
Anmin Zheng
Keyword(s):  
Catalytic Activity ◽  
Direct Conversion ◽  
Methane Activation ◽  
High Catalytic Activity ◽  
Conversion Of Methane ◽  
First Time ◽  
Periodic Dft

The direct conversion of methane to methanol on [Cu(μ-O)M]2+ (M = Cu, Ag, Zn, Au) bimetal centers in ZSM-5 zeolite is investigated using periodic DFT for the first time.

High-efficiency photo-oxidation of thioethers over C60@PCN-222 under air

2019 ◽  
Vol 7 (38) ◽  
pp. 22084-22091 ◽  
Author(s):  
Deng-Yue Zheng ◽  
En-Xuan Chen ◽  
Chun-Rong Ye ◽  
Xiao-Chun Huang
Keyword(s):  
Catalytic Activity ◽  
Photocatalytic Oxidation ◽  
High Efficiency ◽  
Photogenerated Electron ◽  
High Catalytic Activity ◽  
Electron Hole ◽  
Photo Oxidation ◽  
First Time

For the first time, fullerene (C60) was used to enhance the photogenerated electron–hole separation of MOFs as a catalyst and showed high catalytic activity in the photocatalytic oxidation of thioether in air.

Enhanced catalytic activity of low-Pt content nanocatalysts supported on hollow carbon spheres for the ORR in alkaline media

MRS Advances ◽  
2020 ◽  
Vol 5 (57-58) ◽  
pp. 2961-2972
Author(s):  
P.C. Meléndez-González ◽  
E. Garza-Duran ◽  
J.C. Martínez-Loyola ◽  
P. Quintana-Owen ◽  
I.L. Alonso-Lemus ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Anion Exchange ◽  
Average Particle Size ◽  
Synthesis Method ◽  
Alkaline Media ◽  
High Catalytic Activity ◽  
Average Particle ◽  
Carbon Spheres ◽  
Hollow Carbon ◽  
Hollow Carbon Spheres

In this work, low-Pt content nanocatalysts (≈ 5 wt. %) supported on Hollow Carbon Spheres (HCS) were synthesized by two routes: i) colloidal conventional polyol, and ii) surfactant-free Bromide Anion Exchange (BAE). The nanocatalysts were labelled as Pt/HCS-P and Pt/HCS-B for polyol and BAE, respectively. The physicochemical characterization of the nanocatalysts showed that by following both methods, a good control of chemical composition was achieved, obtaining in addition well dispersed nanoparticles of less than 3 nm TEM average particle size (d) on the HCS. Pt/HCS-B contained more Pt0 species than Pt/HCS-P, an effect of the synthesis method. In addition, the structure of the HCS remains more ordered after BAE synthesis, compared to polyol. Regarding the catalytic activity for the Oxygen Reduction Reaction (ORR) in 0.5 M KOH, Pt/HCS-P and Pt/HCS-B showed a similar performance in terms of current density (j) at 0.9 V vs. RHE than the benchmark commercial 20 wt. % Pt/C. However, Pt/HCS-P and Pt/HCS-B demonstrated a 6 and 5-fold increase in mass catalytic activity compared to Pt/C, respectively. A positive effect of the high specific surface area of the HCS and its interactions with metal nanoparticles and electrolyte, which promoted the mass transfer, increased the performance of Pt/HCS-P and Pt/HCS-B. The high catalytic activity showed by Pt/HCS-B and Pt/HCS-P for the ORR, even with a low-Pt content, make them promising cathode nanocatalysts for Anion Exchange Membrane Fuel Cells (AEMFC).

Ordered Intermetallic Nanoparticles with High Catalytic Activity Prepared by an Electrochemically Induced Phase Transformation

2019 ◽  
Author(s):  
Du Sun ◽  
yunfei wang ◽  
Kenneth Livi ◽  
chuhong wang ◽  
ruichun luo ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Diffusion Mechanism ◽  
Reduction Reaction ◽  
Atomic Scale ◽  
High Catalytic Activity ◽  
Ambient Conditions ◽  
Magnetic Devices ◽  
Disordered Alloys ◽  
Ordered Intermetallic ◽  
Intermetallic Nanoparticles

<div> <p>The synthesis of alloys with long range atomic scale ordering (ordered intermetallics) is an emerging field of nanochemistry. Ordered intermetallic nanoparticles are useful for a wide variety of applications such as catalysis, superconductors, and magnetic devices. However, the preparation of nanostructured ordered intermetallics is challenging in comparison to disordered alloys, hindering progress in materials development. We report a process for converting colloidally synthesized ordered intermetallic PdBi<sub>2</sub> to ordered intermetallic Pd<sub>3</sub>Bi nanoparticles under ambient conditions by an electrochemically induced phase transition. The low melting point of PdBi<sub>2</sub> corresponds to low vacancy formation energies which enables the facile removal of the Bi from the surface, while simultaneously enabling interdiffusion of the constituent atoms via a vacancy diffusion mechanism under ambient conditions. The resulting phase-converted ordered intermetallic Pd<sub>3</sub>Bi exhibits 11x and 3.5x higher mass activty and high methanol tolerance for the oxygen reduction reaction compared to Pt/C and Pd/C, respectively,which is the highest reported for a Pd-based catalyst, to the best of our knowledge. These results establish a key development in the synthesis of noble metal rich ordered intermetallic phases with high catalytic activity, and sets forth guidelines for the design of ordered intermetallic compounds under ambient conditions.</p> </div>

Nickel (II) and oxovanadium (IV) complexes supported on MCM-41 mesoporous and their application in catalytic selective sulfide and thiol oxidation

2020 ◽  
Vol 23 ◽  
Author(s):  
Mohsen Nikoorazm ◽  
Maryam Khanmoradi ◽  
Masoumeh Sayadian
Keyword(s):  
Catalytic Activity ◽  
Room Temperature ◽  
Sol Gel ◽  
Reaction Times ◽  
Significant Loss ◽  
Spectral Studies ◽  
High Catalytic Activity ◽  
Catalytic Systems ◽  
Solvent Free Conditions ◽  
Mcm 41

Introduction:: MCM-41 was synthesized using the sol-gel method. Then two new transition metal complexes of Nickel (II) and Vanadium (IV), were synthesized by immobilization of adenine (6-aminopurine) into MCM-41 mesoporous. The compounds have been characterized by XRD, TGA, SEM, AAS and FT-IR spectral studies. Using these catalysts provided an efficient and enantioselective procedure for oxidation of sulfides to sulfoxides and oxidative coupling of thiols to their corresponding disulfides using hydrogen peroxide at room temperature. Materials and Methods:: To a solution of sulfide or thiol (1 mmol) and H2O2 (5 mmol), a determined amount of the catalyst was added. The reaction mixture was stirred at room temperature for the specific time under solvent free conditions. The progress of the reaction was monitored by TLC using n-hexane: acetone (8:2). Afterwards, the catalyst was removed from the reaction mixture by centrifugation and, then, washed with dichloromethane in order to give the pure products. Results:: All the products were obtained in excellent yields and short reaction times indicating the high activity of the synthesized catalysts. Besides, the catalysts can be recovered and reused for several runs without significant loss in their catalytic activity. Conclusion:: These catalytic systems furnish the products very quickly with excellent yields and VO-6AP-MCM-41 shows high catalytic activity compared to Ni-6AP-MCM-41.

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