scholarly journals Atomically Dispersed Transition Metal-Nitrogen-Carbon Bifunctional Oxygen Electrocatalysts for Zinc-Air Batteries: Recent Advances and Future Perspectives

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Fang Dong ◽  
Mingjie Wu ◽  
Zhangsen Chen ◽  
Xianhu Liu ◽  
Gaixia Zhang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Reduction Reaction ◽  
Bifunctional Catalysts ◽  
Future Perspectives ◽  
Manufacturing Costs ◽  
Environmental Friendliness ◽  
Specific Energy Density ◽  
High Metal ◽  
Kinetics Of ◽  
Zinc Air Batteries

AbstractRechargeable zinc-air batteries (ZABs) are currently receiving extensive attention because of their extremely high theoretical specific energy density, low manufacturing costs, and environmental friendliness. Exploring bifunctional catalysts with high activity and stability to overcome sluggish kinetics of oxygen reduction reaction and oxygen evolution reaction is critical for the development of rechargeable ZABs. Atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts possessing prominent advantages of high metal atom utilization and electrocatalytic activity are promising candidates to promote oxygen electrocatalysis. In this work, general principles for designing atomically dispersed M-N-C are reviewed. Then, strategies aiming at enhancing the bifunctional catalytic activity and stability are presented. Finally, the challenges and perspectives of M-N-C bifunctional oxygen catalysts for ZABs are outlined. It is expected that this review will provide insights into the targeted optimization of atomically dispersed M-N-C catalysts in rechargeable ZABs.

Design and synthesis of porous channel-rich carbon nanofibers for self-standing oxygen reduction reaction and hydrogen evolution reaction bifunctional catalysts in alkaline medium

2017 ◽  
Vol 5 (16) ◽  
pp. 7507-7515 ◽  
Author(s):  
Dongxiao Ji ◽  
Shengjie Peng ◽  
Jia Lu ◽  
Linlin Li ◽  
Shengyuan Yang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Oxygen Reduction Reaction ◽  
Hydrogen Evolution ◽  
Carbon Nanofibers ◽  
Hydrogen Evolution Reaction ◽  
Carbon Nanofiber ◽  
Reduction Reaction ◽  
Bifunctional Catalysts ◽  
Free Standing ◽  
Design And Synthesis

Free-standing Fe3C embedded Fe/N doped carbon nanofiber films are prepared based on electrospinning and demonstrate efficient ORR/HER catalytic activity and superior stability.

A Novel Gold Nanoparticle/Poly(AMPS-co-HEMA) Composite Hydrogel for Selective Catalysis

2011 ◽  
Vol 399-401 ◽  
pp. 704-707 ◽  
Author(s):  
Ke Ping Wang ◽  
Song Bai Lin ◽  
Na Na Wang ◽  
Ai Ru Ke
Keyword(s):  
Catalytic Activity ◽  
Reduction Reaction ◽  
Hydrogenation Rate ◽  
Processing Stage ◽  
Composite Gel ◽  
Growth Method ◽  
Selective Catalysis ◽  
Kinetics Of ◽  
Controllable Preparation

A modified seed-mediated growth method was developed for in situ controllable preparation of gold nanoparticles (GNPs) within P(AMPS-co-HEMA) hydrogel networks. When the time of cycles absorbing procedure increased in mother solutions under given temperature during the processing stage, the number of GNPs was significantly increased and networks were utilized for in situ nanoparticles synthesis by reduction of glod ion absorbed. TEM images confirmed that GNPs were between 100 and 200 nm in size and distributed uniformly in gel. The network embedded GNPs also endows the composite gel with selective catalytic activity for selective catalysis in the reduction of nitro compound (2-NP, 3-NP and 4-NP). The kinetics of the reduction reaction were investigated under the same condition, the result showed the GNPs gel system was found to have an excellent catalytic activity and high conversion for 4-NP reduction among nitrophenol homologue, the nitrophenol hydrogenation rate got to 6.63 mol/g min for reducing of 4-NP compared to 3.69 mol/g min, the rate of 2-NP. It was almost zero for 3-NP implying no catalytic activity, even though they were isomeride.

Nanostructured Perovskite LaCo1-xMnxO3 as Bifunctional Catalysts for Rechargeable Metal–Air Batteries

2015 ◽  
Vol 03 (01n02) ◽  
pp. 1540006 ◽  
Author(s):  
Xiaoming Ge ◽  
Bing Li ◽  
Delvin Wuu ◽  
Afriyanti Sumboja ◽  
Tao An ◽  
...  
Keyword(s):  
Rotating Disk ◽  
Bifunctional Catalyst ◽  
Reduction Reaction ◽  
Rotating Disk Electrode ◽  
Bifunctional Catalysts ◽  
X Ray Diffraction ◽  
Practical Utilization ◽  
Cathode Catalysts ◽  
Hydrothermal Methods ◽  
Zinc Air Batteries

Bifunctional catalyst that is active for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is one of the most important components of rechargeable metal–air batteries. Nanostructured perovskite bifunctional catalysts comprising La , Co and Mn ( LaCo 1-x Mn x O 3, LCMO ) are synthesized by hydrothermal methods. The morphology, structure and electrochemical activity of the perovskite bifunctional catalysts are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and rotating disk electrode (RDE) techniques. Nanorod, nanodisc and nanoparticle are typical morphologies of LCMO . The electrocatalytic activity of LCMO is significantly improved by the addition of conductive materials such as carbon nanotube. To demonstrate the practical utilization, LCMO in the composition of LaCo 0.8 Mn 0.2 O 3( LCMO82 ) is used as air cathode catalysts for rechargeable zinc–air batteries. The battery prototype can sustain 470 h or 40 discharge–charge cycles equivalent.

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>

Study of nickel-molybdenum catalysts for methanation of carbon monoxide

1980 ◽  
Vol 45 (3) ◽  
pp. 783-790 ◽  
Author(s):  
Petr Taras ◽  
Milan Pospíšil
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Mixed Oxides ◽  
Minor Component ◽  
Fast Neutrons ◽  
Scanning Calorimetry ◽  
Low Concentrations ◽  
Γ Rays ◽  
Molybdenum Catalysts ◽  
Kinetics Of

Catalytic activity of nickel-molybdenum catalysts for methanation of carbon monoxide and hydrogen was studied by means of differential scanning calorimetry. The activity of NiMoOx systems exceeds that of carrier-free nickel if x < 2, and is conditioned by the oxidation degree of molybdenum, changing in dependence on the composition in the region Mo-MoO2. The activity of the catalysts is adversely affected by irradiation by fast neutrons, dose 28.1 Gy, or by γ rays using doses in the region 0.8-52 kGy. The system is most susceptible to irradiation in the region of low concentrations of the minor component (about 1 mol.%). The dependence of changes in catalytic activity of γ-irradiated samples on the dose exhibits a maximum in the range of 2-5 kGy. The changes in catalytic activity are stimulated by the change of reactivity of the starting mixed oxides, leading to different kinetics of their reduction and modification of their adsorption properties. The irradiation of the catalysts results in lowered concentration of the active centres for the methanation reaction.

Catalytic activity of rhodium(I) complexes containing (ω-trimethylsilylalkyl)diphenylphosphines

1980 ◽  
Vol 45 (8) ◽  
pp. 2219-2223 ◽  
Author(s):  
Marie Jakoubková ◽  
Martin Čapka
Keyword(s):  
Catalytic Activity ◽  
Nmr Spectroscopy ◽  
Ir Spectroscopy ◽  
Electron Density ◽  
Phosphorus Atom ◽  
Proton Acceptor ◽  
Trimethylsilyl Group ◽  
Kinetics Of

Kinetics of homogenous hydrogenation of 1-heptene catalysed by rhodium(I) complexes prepared in situ from μ,μ'-dichloro-bis(cyclooctenerhodium) and phosphines of the type RP(C6H5)2 (R = -CH3, -(CH2)nSi(CH3)3; n = 1-4) have been studied. The substitution of the ligands by the trimethylsilyl group was found to increase significantly the catalytic activity of the complexes. The results are discussed in relation to the electron density on the phosphorus atom determined by 31P NMR spectroscopy and to its proton acceptor ability determined by IR spectroscopy.

Polymer structure and catalytic activity of ion exchangers

1981 ◽  
Vol 46 (7) ◽  
pp. 1577-1587 ◽  
Author(s):  
Karel Jeřábek
Keyword(s):  
Catalytic Activity ◽  
Ethyl Acetate ◽  
Active Sites ◽  
Crosslinking Agent ◽  
Reaction Medium ◽  
Polymer Structure ◽  
Local Concentration ◽  
Ion Exchangers ◽  
Styrene Divinylbenzene ◽  
Kinetics Of

Catalytic activity of ion exchangers prepared by partial sulphonation of styrene-divinylbenzene copolymers in reesterifications of ethyl acetate by methanol and propanol, hydrolysis of ethyl acetate and in synthesis of bisphenol A has been compared with data on polymer structure of these catalysts and with distribution of the crosslinking agent, divinylbenzene, calculated from literature data on kinetics of copolymerisation of styrene with divinylbenzene. It was found that the polymer structure of ion exchangers influences catalytic activity predominantly by changing the local concentration of acid active sites. The results obtained indicated that the effect of transport phenomena on the rate of catalytic reactions does not depend on the degree of swelling of the ion exchangers in reaction medium but it is mainly dependent on the relative affinity of reaction components to the acid groups or to the polymer skeleton.

In-situ stabilization of silver nanoparticles in polymer hydrogels for enhanced catalytic reduction of macro and micro pollutants

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Luqman Ali Shah ◽  
Rida Javed ◽  
Mohammad Siddiq ◽  
Iram BiBi ◽  
Ishrat Jamil ◽  
...  
Keyword(s):  
Catalytic Reduction ◽  
Thermo Gravimetric Analysis ◽  
Activation Parameters ◽  
Reduction Reaction ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
In Situ Stabilization ◽  
Hybrid Hydrogels ◽  
Kinetics Of

AbstractThe in-situ stabilization of Ag nanoparticles is carried out by the use of reducing agent and synthesized three different types of hydrogen (anionic, cationic, and neutral) template. The morphology, constitution and thermal stability of the synthesized pure and Ag-entrapped hybrid hydrogels were efficiently confirmed using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and thermo gravimetric analysis (TGA). The prepared hybrid hydrogels were used in the decolorization of methylene blue (MB) and azo dyes congo red (CR), methyl Orange (MO), and reduction of 4-nitrophenol (4-NP) and nitrobenzene (NB) by an electron donor NaBH4. The kinetics of the reduction reaction was also assessed to determine the activation parameters. The hybrid hydrogen catalysts were recovered by filtration and used continuously up to six times with 98% conversion of pollutants without substantial loss in catalytic activity. It was observed that these types of hydrogel systems can be used for the conversion of pollutants from waste water into useful products.

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