Related Experiment Video
Updated: Mar 13, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
16.2K
Modulation of the exfoliated graphene work function through cycloaddition of nitrile imines
Myriam Barrejón1, María J Gómez-Escalonilla1, José Luis G Fierro2
1Universidad de Castilla-La Mancha, Instituto de Nanociencia, Nanotecnología y Materiales Moleculares (INAMOL), 45071, Toledo, Spain. Fernando.Langa@uclm.es.
Physical Chemistry Chemical Physics : PCCP
|October 27, 2016
Summary
Functionalizing graphene with organic molecules via 1,3-dipolar cycloaddition is now feasible. This method allows tuning electronic properties like work function and band gap by modifying organic addends on the graphene surface.
Area of Science:
- Materials Science
- Organic Chemistry
- Physical Chemistry
Background:
- Graphene's unique electronic properties make it attractive for advanced applications.
- Functionalization is key to tailoring graphene's properties.
- Efficient and controlled methods for graphene functionalization are needed.
Purpose of the Study:
- To investigate the feasibility of 1,3-dipolar cycloaddition for graphene functionalization.
- To explore the modulation of electronic properties of functionalized graphene.
- To develop a rapid and effective method for creating graphene-organic hybrids.
Main Methods:
- Density functional theory (DFT) calculations to assess reaction feasibility.
- Functionalization of exfoliated few-layer graphene using hydrazone-derived nitrile imines.
- Microwave irradiation for rapid reaction kinetics.
- Characterization using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA).
- Measurement of work function and band gap using Ultraviolet Photoelectron Spectroscopy (UPS).
Main Results:
- The 1,3-dipolar cycloaddition reaction between nitrile imines and graphene was confirmed as feasible.
- Few-layer graphene was successfully functionalized with organic addends.
- Characterization confirmed the successful anchoring of organic molecules onto the graphene surface.
- Work function and band gap of the graphene hybrids were successfully modulated.
- Modulation was achieved by altering the electronic properties of the organic addends and the functionalization degree.
Conclusions:
- 1,3-dipolar cycloaddition is a viable method for functionalizing graphene.
- The electronic properties of graphene can be tuned by selecting appropriate organic addends.
- This approach offers a pathway to engineer graphene-based materials with desired electronic characteristics.
Related Concept Videos
01:23Aldehydes and Ketones with Amines: Imine Formation Mechanism
8.8K
Imine formation involves the addition of carbonyl compounds to a primary amine. It begins with the generation of carbinolamine through a series of steps involving an initial nucleophilic attack and then several proton transfer reactions. The second part includes the elimination of water, as a leaving group, to give the imine.
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
8.8K
01:16Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview
7.2K
Primary amines react with carbonyl compounds—aldehydes and ketones—to generate imines. Imines consist of a C=N double bond and are named Schiff bases after its discoverer—the German chemist Hugo Schiff. On the other hand, secondary amines react with carbonyl compounds to give enamines. In enamines, the presence of a C=C double bond adjacent to the nitrogen atom leads to the delocalization of the lone pair.
7.2K
00:57Nitriles to Ketones: Grignard Reaction
6.4K
Organomagnesium halides, commonly known as Grignard reagents, convert nitriles to ketones and proceed through a nucleophilic acyl substitution. Nitriles react with a Grignard reagent, followed by an aqueous acid, to yield ketones. The reaction introduces a new carbon–carbon bond. The alkyl–magnesium bond in the Grignard reagent is highly polar, so the alkyl carbon develops a carbanionic character and acts as a nucleophile.
The mechanism begins with a nucleophilic attack by the Grignard...
The mechanism begins with a nucleophilic attack by the Grignard...
6.4K
01:12Preparation of Nitriles
2.8K
One of the common methods to prepare nitriles is the dehydration of amides. This method requires strong dehydrating agents like phosphorous pentoxide or boiling acetic anhydride for converting amides to nitriles. Another reagent namely, thionyl chloride also accomplishes the dehydration of amides, where amide acts as a nucleophile. The first step of the mechanism involves the nucleophilic attack by the amide on the thionyl chloride to form an intermediate. In the next step, the electron pairs...
2.8K
01:16Cycloaddition Reactions: MO Requirements for Thermal Activation
5.0K
Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.
5.0K
01:14Aldehydes and Ketones with Amines: Enamine Formation Mechanism
8.3K
Enamine formation involves the addition of carbonyl compounds to a secondary amine through a series of reactions. The mechanism begins with the generation of carbinolamine, a nucleophilic attack followed by several proton transfer reactions. The hydroxyl group of the carbinolamine is converted into water to make a better leaving group that can push the reaction forward by eliminating a water molecule. In enamine formation, the last step involves the abstraction of a proton from the α carbon to...
8.3K