Self-regeneration of a Ni–Cu alloy catalyst during a three-way catalytic reaction

2019 ◽  
Vol 21 (35) ◽  
pp. 18816-18822 ◽  
Author(s):  
Hiroyuki Asakura ◽  
Tetsuo Onuki ◽  
Saburo Hosokawa ◽  
Nozomi Takagi ◽  
Shigeyoshi Sakaki ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Catalytic Reaction ◽  
High Catalytic Activity ◽  
Cu Alloy ◽  
Alloy Catalyst

Ni–Cu alloy supported on γ-Al22O3 catalysts exhibit high catalytic activity and durability for a three-way catalytic reaction under both oxidative and reductive conditions because of their self-regenerating feature.

scholarly journals Low platinum alloy catalyst PtCo3 obtaining high catalytic activity and stability with great water and CO2 resistance for catalytic oxidation of toluene

Fuel ◽  
2022 ◽  
Vol 307 ◽  
pp. 121794
Author(s):  
Jianwu Zou ◽  
Yankun Du ◽  
Rongjia Fang ◽  
Xiaoshuang Duan ◽  
Yangjia Liu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Catalytic Oxidation ◽  
High Catalytic Activity ◽  
Platinum Alloy ◽  
Alloy Catalyst

scholarly journals Amorphous Alloy: Promising Precursor to Form Nanoflowerpot

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Guo Lan ◽  
Zhiqiang Xie ◽  
Zhenwei Huang ◽  
Shengchen Yang ◽  
Xuhai Zhang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Amorphous Alloy ◽  
Amorphous Alloys ◽  
High Catalytic Activity ◽  
Cu Alloy ◽  
Nanoporous Copper ◽  
Highly Dispersed ◽  
Oxidation Of Glucose

Nanoporous copper is fabricated by dealloying the amorphous Ti2Cu alloy in 0.03 M HF electrolyte. The pore and ligament sizes of the nanoporous copper can be readily tailored by controlling the dealloying time. The as-prepared nanoporous copper provides fine and uniform nanoflowerpots to grow highly dispersed Au nanoflowers. The blooming Au nanoflowers in the nanoporous copper flowerpots exhibit both high catalytic activity and stability towards the oxidation of glucose, indicating that the amorphous alloys are ideal precursors to form nanoflowerpot which can grow functional nanoflowers.

One-Pot Synthesis of CeO2-Supported Pd-Cu-Alloy Nanocubes with High Catalytic Activity

2013 ◽  
Vol 19 (25) ◽  
pp. 8053-8057 ◽  
Author(s):  
Kyu-Hwan Park ◽  
Young Wook Lee ◽  
Yena Kim ◽  
Shin Wook Kang ◽  
Sang Woo Han
Keyword(s):  
Catalytic Activity ◽  
High Catalytic Activity ◽  
One Pot ◽  
One Pot Synthesis ◽  
Cu Alloy ◽  
Supported Pd

scholarly journals Synthesis of Au–Cu Alloy Nanoparticles as Peroxidase Mimetics for H2O2 and Glucose Colorimetric Detection

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 343
Author(s):  
Cun Liu ◽  
Sang Hyuk Im ◽  
Taekyung Yu
Keyword(s):  
Catalytic Activity ◽  
Limit Of Detection ◽  
Colorimetric Detection ◽  
Molar Ratio ◽  
High Catalytic Activity ◽  
Alloy Nanoparticles ◽  
Research Fields ◽  
Cu Alloy ◽  
Bimetallic Alloy ◽  
Mediated Oxidation

The detection of hydrogen peroxide (H2O2) is essential in many research fields, including medical diagnosis, food safety, and environmental monitoring. In this context, Au-based bimetallic alloy nanomaterials have attracted increasing attention as an alternative to enzymes due to their superior catalytic activity. In this study, we report a coreduction synthesis of gold–copper (Au–Cu) alloy nanoparticles in aqueous phase. By controlling the amount of Au and Cu precursors, the Au/Cu molar ratio of the nanoparticles can be tuned from 1/0.1 to 1/2. The synthesized Au–Cu alloy nanoparticles show good peroxidase-like catalytic activity and high selectivity for the H2O2-mediated oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB, colorless) to TMB oxide (blue). The Au–Cu nanoparticles with an Au/Cu molar ratio of 1/2 exhibit high catalytic activity in the H2O2 colorimetric detection, with a limit of detection of 0.141 μM in the linear range of 1–10 μM and a correlation coefficient R2 = 0.991. Furthermore, the Au–Cu alloy nanoparticles can also efficiently detect glucose in the presence of glucose oxidase (GOx), and the detection limit is as low as 0.26 μM.

One-step green synthesis of composition-tunable Pt–Cu alloy nanowire networks with high catalytic activity for 4-nitrophenol reduction

2018 ◽  
Vol 47 (48) ◽  
pp. 17461-17468 ◽  
Author(s):  
Yingfang Zhang ◽  
Yan Xia ◽  
Saisai Yan ◽  
Jia Han ◽  
Yifan Chen ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Green Synthesis ◽  
High Catalytic Activity ◽  
Cu Alloy ◽  
Nitrophenol Reduction ◽  
One Step ◽  
Nanowire Networks

Self-interconnecting Pt–Cu alloy NWNs with high catalytic activity for 4-nitrophenol reduction were synthesized via a facile, one-step and eco-friendly approach.

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.

Mechanisms of methane decomposition and carbon species oxidation on the Pr0.42Sr0.6Co0.2Fe0.7Nb0.1O3−σ electrode with high catalytic activity

2015 ◽  
Vol 3 (45) ◽  
pp. 22816-22823 ◽  
Author(s):  
Peng Zhang ◽  
Guoqing Guan ◽  
Deni S. Khaerudini ◽  
Xiaogang Hao ◽  
Chunfeng Xue ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Carbon Deposition ◽  
Methane Decomposition ◽  
High Catalytic Activity ◽  
Carbon Species

Carbon deposition characteristics on PSCFN and Ni–YSZ due to thermal CH4 decomposition are investigated by using TPR technique.

Sign in / Sign up

Export Citation Format

Share Document