Allotropy
- Allotropy or allotropism is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.
Allotropes of carbon
- Carbon is capable of forming many allotropes (structurally different forms of the same element) due to its valency. Well-known forms of carbon include diamond and graphite.
Allotropes of carbon
- Diamond, graphite and fullerenes (substances that include nanotubes and ‘buckyballs’, such as buckminsterfullerene) are three allotropes of pure carbon.
Diamond
- Diamond is extremely hard and has a high melting point.
- For this reason, it is very useful in cutting tools.
- The cutting edges of discs used to cut bricks and concrete are tipped with diamonds.
- Heavy-duty drill bits – such as those used in the oil exploration industry to drill through rocks
Graphite
- It is used in pencil leads because layers easily slide onto the paper, leaving a black mark. It is a component of many lubricants, for example, bicycle chain oil.
- Graphite is insoluble in water.
- It has a high melting point and is a good conductor of electricity, which makes it a suitable material for the electrodes needed in electrolysis.
Nanotubes
- Nanotubes are a type of fullerene and are molecular-scale tubes of carbon arranged similarly to the layers in graphite.
Carbon nanotubes (CNTs)
- Carbon nanotubes (CNTs) are cylindrical molecules that consist of rolled-up sheets of single-layer carbon atoms (graphene).
- They can be single-walled (SWCNT) with a diameter of less than 1 nanometer (nm) or multi-walled (MWCNT), consisting of several concentrically interlinked nanotubes, with diameters reaching more than 100 nm.
Applications:
- Used in electric wires to reduce losses
- It can replace silicon made transistors as they are small and emit less heat and it can revolutionise electronics
- Can be used in solar cell