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By means of first principles calculations we show that graphene binds strongly to native iron surfaces highly reducing their surface energy.
In contrast to graphene, segregation of the substitutional iron impurities in graphite under ambient conditions is not energetically favorable.
The resultant iron-iron oxide dispersed graphene was highly porous, robust and attractive for a variety of potential applications.
Magnetic, Mossbauer and Raman spectroscopy measurements indicate that graphene can interact with iron oxide.
Calculated values of formation energies for the substitutional iron impurities suggest that iron is more destructive for graphite than for graphene.
According to this work graphene reduces the adhesion of iron interfaces by reducing the surface energy thanks to a passivation effect.
Calculations and experimental results show that iron strongly modifies the graphene band structure and lifts its π band spin degeneracy.
Thermal annealing leads to reduction of the iron oxide to pure iron and provides a means to tailor the magnetic properties of the multilayer graphene coated nanoparticles which are attractive as units for hyperthermia th...
At the same time they show a tendency of graphene to passivate the native iron surfaces that are exposed during sliding as a consequence of wear.
The quality and uniformity of the graphene grown on low-cost iron-group metals determine whether graphene can be put into the mass productions or not.

Related Questions

What are the sources of Iron?5 answersIron can be sourced from both plant-based and animal-based foods. Plant-based sources include legumes like beans, lentils, soybeans, lupin, spinach, and dehydrated fruits, which are rich in nonhemic iron with variable bioavailability. On the other hand, animal-based sources of iron include red meat from various animals like bovine, camel, goat, and poultry, with liver containing the highest iron concentrations. Additionally, quail eggs are noted for their high iron content. Early humans historically accessed iron from meteoric and native iron sources, with meteorites containing nickel and being used for iron production in ancient times. Furthermore, bacteria acquire iron through various mechanisms, utilizing iron and heme acquisition systems involving direct contact or the release of siderophores and hemophores to scavenge iron from the environment.
What are the advantages of using graphene in metal complexes?5 answersGraphene has several advantages when used in metal complexes. Firstly, graphene-based materials have unique physicochemical properties such as a high theoretical specific surface area, high electrical conductivity, and outstanding acid-base resistance properties. These properties make graphene an excellent support material for metal complexes, enhancing their catalytic activity and stability in various reactions, including C-C bond formation. Additionally, the two-dimensional structure of graphene allows for site isolation and synergistic interactions between the metal complexes and graphene, further enhancing the catalytic activity. Furthermore, graphene's excellent mechanical properties, robust chemical inertness, thermal stability, and self-lubricating nature make it an effective reinforcement for metal matrix composites. Overall, the use of graphene in metal complexes offers improved catalytic performance and mechanical properties, making it a promising material for various applications.
How can we prepare graphene from rice straw using ferrocene?5 answersGraphene can be prepared from rice straw using different methods. One method involves activating rice straw ash (RSA) using potassium hydroxide (KOH) at high temperatures, such as 700 oC or 800 oC, with specific impregnation ratios. Another method involves firing rice-wheat straw into char powder without oxygen, activating the char powder, and graphitizing it at temperatures between 2400 to 2600 degrees Celsius. Additionally, lignin residue produced by straw fermentation or straw acid hydrolysis can be used as a carbon source to synthesize graphene. It is important to note that none of the abstracts mention the use of ferrocene in the preparation of graphene from rice straw. Therefore, there is no information available on preparing graphene from rice straw using ferrocene in the provided abstracts.
How to clean blood of graphene ?5 answersGraphene can be cleaned from blood using various methods. One method involves using an ultrasonic processing (UP) step to etch copper and clean the bottom surface of graphene. Another method involves using a device with graphene sheets that have apertures to isolate substances from blood. Additionally, a graphene stripping device can be used to obtain large-area defect-free graphene by implementing rapid directional arrangement of graphite flakes and playing a shearing effect. Furthermore, a superhydrophobic surface made of graphene and titanium dioxide nanoparticles can be dip-coated on a film to enhance biocompatibility and inhibit biofilm formation. Lastly, a large-scale clean preparation method for graphene involves dispersing graphite raw material in a suspension, subjecting it to ultrasonic treatment, and then stripping off the graphene under a high-speed air flow.
Does charcoal contain graphene?9 answers
Will graphene set off a metal detector?10 answers

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5 answers
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The red coloration of laboratory magnets is primarily due to the presence of red magnetic powders, specifically gamma-Fe2O3, which exhibit coercive force within a specific range and are combined with red tar dyes like Rhodamine B or Lake Red C. Additionally, the magneto-optical properties of alpha-Fe2O3, such as hematite, can appear more red in an applied magnetic field, especially during the spin-flop transition, indicating a connection between charge, magnetism, and coloration in transition metal oxides. These red magnetic powders are obtained by mixing compounds of magnesium, zinc, and iron in specific proportions and calcining the mixture, resulting in a ferromagnetic metallic oxide composition that contributes to the red coloration of the magnets.
The red-shifting of 2D Raman band position of graphene is attributed to doping of graphene??
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The red-shifting of the 2D Raman band position in graphene is not solely attributed to doping. Research indicates that the Raman 2D peak position and splitting can be correlated with charge density variations in graphene, with lower charge densities resulting in larger 2D peak-splits. Additionally, the interplay between graphene and its supporting substrate, such as Cu grains, can also influence the Raman bands. For instance, (110) Cu grains exhibit anomalous shifts in the graphene 2D Raman band due to weak graphene-Cu coupling, impacting the Raman scattering processes. Therefore, while doping can play a role in the Raman characteristics of graphene, factors like charge density variations and substrate interactions also significantly contribute to the observed red-shifting of the 2D Raman band position.
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Can graphene oxide have antibacterial properties?
4 answers
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