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Graphite oxide was found to be a highly efficient, reusable and cost-effective heterogeneous catalyst for the direct metal-free transformation of amines to afford the corresponding imines under mild and neat conditions with molecular oxygen as the terminal oxidant.
The developed catalyst is air-stable, inexpensive, easy to prepare, easy to recover by simple filtration and can be reused without appreciable loss of activity.
Compared to other catalysts supported on magnetic particles, this catalyst is very simple to prepare even in large quantities and is easy to recover completely owing to the high magnetic saturation of the Co nucleus.
Here, the authors prepare a high-performing catalyst that is supported on graphitic tubes, containing Fe, Co and Cu, and requires only a small amount of Pt.
The pre-treatment of graphite supports with tin-palladium chloride solutions is shown to be advantageous for subsequent catalyst deposition because of multifold effects.
Meanwhile, this research also provides another route to prepare a catalyst with ultra low noble metal on WC/RGO for solving the problem of high cost of the catalyst.
This Fe-N-C catalyst shows a much improved catalytic activity compared with that synthesized from graphite granules.
In particular, the improved stability and good activity observed for the catalyst adsorbed on graphite powder embedded in a Nafion film shows that this is a promising H2 production system that can be assembled at minimal cost and effort.

Related Questions

How to synthesis porous graphene?4 answersPorous graphene can be synthesized through various methods. One approach is the introduction of nanopores into graphene-based materials, which can be achieved by controlling the size, morphology, density, and location of the nanopores. Another method involves the design and synthesis of nanoporous graphene from organic precursor molecules, such as 2-amino-3-hydroxypyridine and phloroglucinol, which can generate pores during heat treatment. Additionally, graphene-like porous carbon can be synthesized from walnut shell through carbonization and thermochemical activation processes, resulting in graphene-like porous carbon with high specific surface area and potential applications in supercapacitors, lithium-ion batteries, and desalination membranes. Furthermore, a novel 3D porous graphene can be synthesized from maleic acid through a one-step carbonization process, using sodium carbonate as the skeletal substrate, resulting in well-defined pores and enhanced adsorption and electrochemical properties.
How to exfoliate graphite?4 answersExfoliating graphite can be achieved through various methods. One approach is to use a plasma process to exfoliate and functionalize graphite flakes. Another method involves passing an electric current through an electrochemical reaction system containing graphite and an electrolyte solution, followed by a peeling operation. Additionally, vein graphite can be electrochemically exfoliated and further exfoliated by ultrasonic vibration using inexpensive and nontoxic aqueous black tea solution. Electrochemical exfoliation in an ammonium sulfate solution has also been shown to produce two- to three-layer graphene. These methods offer different approaches to exfoliating graphite, providing options for producing exfoliated graphite with varying thickness and properties.
How to dissolve graphite?2 answersGraphite can be dissolved using various methods. One method involves using a purification agent and subjecting the graphite to ultrasonic vibration and microwave heating. Another method involves high-pressure alkaline leaching, where graphite concentrates are mixed with a sodium hydroxide alkaline solution and subjected to high temperature and continuous stirring. Additionally, alkaline graphite intercalation compounds can be prepared by combining flake graphite with K2Cr2O7, concentrated H2SO4, and NaOH, which breaks the bonds and forms spaces between the graphene planes. A short process purification method involves crushing, grinding, and flotation steps, which improve dissociation efficiency and optimize the flotation effect. Another process involves heating crude or prepurified natural graphite with an aqueous alkaline solution under pressure, followed by acid treatment and washing.
How do you prepare graphene coating?10 answers
How to etch graphene?10 answers
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What are the list of natural and synthetic CNTs nanofiller in polymer nanocomposite for prosthetic applications?
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How ammonia works as hydrogen carrier?
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Why BTC is not dissolving in water?
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The reason why BTC (benzenetricarboxylate) does not dissolve in water is due to its poor water stability, as highlighted in various research papers. Cu-BTC, a metal-organic framework (MOF) containing BTC, is known to collapse under humid conditions. Studies have shown that the incorporation of stable materials like activated carbon into Cu-BTC enhances its water stability, preventing structural collapse when exposed to water molecules. Additionally, research on ILs (ionic liquids)/Cu-BTC composites revealed that the presence of ILs can retard the decomposition of Cu-BTC upon water exposure, indicating a protective effect against water-induced degradation. These findings emphasize the critical role of water stability in maintaining the structural integrity of MOFs like Cu-BTC, preventing their dissolution in water.
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