What Are Fullerenes? Definition, Structure & Key Applications
Compounds of Carbon are everywhere. They are in the pencil that you write with, they are in the table that you have your book on and they are also in the same body that is keeping you alive. They are everywhere. One very interesting topic in the study of carbon compounds is the one of Fullerene. As you all might already know from the first time you read about carbon compounds, fullerene is an allotrope of Carbon. And that it has a very peculiar structure, to say the least.
Fullerene resembles the structure of a football. The entire compound looks exactly like the ball that the world likes to play within a sport that is celebrated everywhere we go. Fullerene not only has a very interesting structure but it also has very interesting properties. Its properties and other details are what we will be focussing on through this article from Vedantu. We will be making sure that by the end of this article, you realize what fullerene is and what exactly it is like and why we want you to appreciate this amazing carbon allotrope.
But before you start reading this entire article, we would like to ask you to get your notepad and the pen out so that you can start taking notes along the way and make the most out of this article. Vedantu wants you to understand this concept fully in the very first go because this not only will save your time but will also provide you with a very good grip on the knowledge that you will apply in the next chemistry exam that you take. So sit back, read and understand this brilliant article on the most beautiful allotrope of carbon, Fullerene (no offense graphite).
Fullerene is one of the allotropic forms of carbon. The other name of fullerene is buckminsterfullerene. In this allotropic form of carbon, the carbon molecules are arranged in a series and form a cage-like structure. This structure of fullerene is hollow. In this allotropic form when the carbon molecules are arranged in a cylindrical form, they form a tube-like structure. These tube-like structures are known as carbon nanotubes.
Fullerene Structure
In nature, fullerenes, especially the C60 sphere, are highly symmetrical. Fullerenes have a similar structure to graphite, which is made up of a sheet of connected hexagonal rings, but they have pentagonal (or sometimes heptagonal) rings that prevent the sheet from being planar. Buckyballs and buckytubes are terms used to describe them depending on their shape. Cylindrical fullerenes are referred to as nanotubes. C60 is the most common fullerene, with no two pentagons sharing an edge. A C60 molecule's average carbon-carbon bond length is 1.44 angstrom.
Properties of Fullerene
Physical Properties of Fullerene
Fullerene shows variation in behaviour and structure on changing the temperature. At a higher temperature, the fullerene is converted into the C70 form.
Fullerene shows the change in the structure under different pressures.
The ionization enthalpy of fullerene is 7.61 electron volts.
The electron affinity of fullerene is 2.6 to 2.8 electrons volts.
Chemical Properties of Fullerene
Fullerene (C60) resembles an electrophile in chemical reactions.
Fullerene can act as an electron acceptor group. It can easily accept three electrons or more. Therefore, it can behave as an oxidizing agent.
Fullerenes are doped with alkali or alkaline earth metals so that they can exhibit superconductivity properties.
Ferromagnetism is a property of fullerene.
Carbon molecules abound in fullerene. As a result, it's very soluble in organic solvents.
Types of Fullerene
Buckminsterfullerene
Endohedral Fullerene
Herbal fullerenes
Buckyball Clusters
Nanotubes
Megatubes
Linked bucky ball and chain Dimers
Herbal fullerenes
Some of the Forms of Fullerenes are Discussed Below
Buckyball Clusters
These forms of fullerenes are the smallest member of the fullerene group. Its structural formula is C20. These fullerenes are unsaturated versions of dodecahedra.
Nanotubes
These forms of fullerene are hollow tubes of very small dimensions, having single or multiple walls. These types of fullerenes play an important role in the electronics industry.
Megatubes
These are larger in diameter than the nanotubes. These types of fullerenes are prepared with walls of different thicknesses. It is potentially used for the transport of a variety of molecules of different sizes.
Linked Ball and Chain Dimer
In this form of fullerene, two buckyballs are linked by a carbon chain.
Buckminsterfullerene
Buckminster fullerene is the most common form of fullerene. It exists in C60 form.
Uses of Fullerene
The use of buckminsterfullerene is based on its chemical properties and its physical properties. Let us discuss the use of fullerene.
Fullerene is used as conductors.
It can be used as an absorbent for gases.
Fullerene is used as a lubricant.
Some forms of fullerenes are used in making cosmetics-related materials.
Carbon nanotubes are made up of graphene sheets.
Some forms of fullerenes are used in biomedical applications.
Fullerenes are used in making carbon nanotubes-based fabrics and fibers.
Did You Know?
Fullerenes are of different types C60, C70, C80, and C90. It can exist in various forms, depending on the number of carbon atoms present in the molecule.
The fullerene was discovered by a scientist named Buckminster. Therefore, it is named buckminsterfullerene.
Conclusion
Fullerene or the Buckminsterfullerene is one of the most intriguing concepts that you will come across in your pursuit of studying and understanding what carbon compounds are. We hope that through this article you were able to understand everything that this compound of carbon is about and was able to figure out why it is the way it is. Fullerene has a lot of interesting properties and we hope that you were able to enjoy learning from this article as much as we enjoyed making it for you. The team at Vedantu thanks you for the faith that you have put in us and we hope that this article was helpful.
FAQs on Fullerene: Properties, Types, and Uses in Chemistry
1. What is a fullerene and why is it often called a “buckyball”?
A fullerene is a distinct form (allotrope) of carbon, where carbon atoms are arranged to form a hollow sphere, ellipsoid, or tube. The most famous example, C60, has a spherical shape resembling a soccer ball. It is commonly called a “buckyball” or “buckminsterfullerene” in honour of the architect Buckminster Fuller, who designed geodesic domes with a similar geometric structure.
2. What is the general structure of a fullerene molecule?
A fullerene molecule is composed of carbon atoms linked together in a network of interconnected hexagonal and pentagonal rings. While graphite consists only of hexagonal rings in flat sheets, the presence of pentagonal rings in fullerenes introduces curvature, forcing the structure to close into a cage. Cylindrical variations of fullerenes are known as carbon nanotubes.
3. How many pentagonal and hexagonal rings are in the C60 fullerene, and why are both types of rings necessary for its structure?
The C60 fullerene molecule has a precise arrangement of rings:
- It contains 20 hexagonal rings.
- It contains 12 pentagonal rings.
4. What are the key physical and chemical properties of fullerenes?
Fullerenes have several unique properties as per the NCERT syllabus for the 2025-26 session:
- Physical Properties: They are dark, needle-like crystalline solids. Fullerenes are not soluble in water but can dissolve in organic solvents like toluene and carbon disulphide to produce coloured solutions (e.g., C60 gives a magenta solution).
- Chemical Properties: Due to the strain from their curved structure, fullerenes are moderately reactive. They behave as electrophiles (electron-deficient species) and can undergo addition reactions with nucleophiles. They can also accept electrons to form anions, making them effective oxidising agents.
5. How do fullerenes differ from other carbon allotropes like diamond and graphite?
Fullerenes differ significantly from diamond and graphite in their atomic arrangement and hybridisation:
- vs. Diamond: Diamond has a rigid three-dimensional lattice where each carbon atom is sp³ hybridised and bonded to four others. In contrast, fullerenes are hollow cage-like molecules where carbon atoms are sp² hybridised.
- vs. Graphite: Graphite consists of flat, two-dimensional sheets of sp² hybridised carbons in hexagonal rings. Fullerenes are also composed of sp² carbons but include pentagonal rings, which cause the structure to curve and form a closed, three-dimensional molecule rather than flat layers.
6. What is the fundamental difference between a fullerene and graphene?
While both are allotropes of carbon made of sp²-hybridised atoms, their dimensionality is the key difference. Graphene is a single, perfectly flat, two-dimensional (2D) sheet of carbon atoms arranged in a honeycomb lattice. A fullerene, such as C60, can be considered a zero-dimensional (0D) molecule, formed when a carbon sheet is wrapped into a closed sphere. Essentially, you can think of a buckyball as a graphene sheet that has been curved and sealed by introducing pentagons.
7. What are some important real-world applications of fullerenes?
The unique structure of fullerenes gives them potential for several advanced applications:
- Superconductivity: When doped with alkali metals (e.g., potassium in K₃C₆₀), fullerenes can become superconductors at certain temperatures.
- Medical Science: Their hollow cage can be used for drug delivery systems, and their properties are studied for use as MRI contrast agents and in photodynamic therapy.
- Advanced Materials: They are used as lubricants because of their ball-bearing-like shape at the molecular level and as catalysts in various industrial chemical reactions.
- Electronics: Fullerenes are used in organic solar cells (photovoltaics) and as components in some next-generation electronic devices.
8. Why are fullerenes considered electron-deficient, and how does this affect their chemical reactivity?
In a fullerene, the carbon atoms are sp² hybridised, but the molecule is not flat. The strain caused by the curvature of the cage results in hybridisation that is intermediate between sp² and sp³. This pulls the electron density towards the interior of the cage, leaving the outer surface relatively electron-deficient or electrophilic. This property dictates its reactivity; fullerenes readily react with nucleophiles (electron-rich species) and easily undergo addition reactions, behaving more like an electron-poor alkene than a stable aromatic compound.
9. Is it possible to trap other atoms inside a fullerene cage, and what is the significance of this?
Yes, it is possible to trap atoms, ions, or small molecules inside the hollow structure of a fullerene. These resulting compounds are known as endohedral fullerenes. They are denoted with the notation M@Cn, where 'M' is the trapped species (e.g., N@C60 for a nitrogen atom inside a C60 cage). Their significance is immense, as they allow scientists to study the properties of single, isolated atoms in a unique chemical environment, which has potential applications in quantum computing, atomic clocks, and as highly sensitive medical imaging agents.
