The exhibition is an interactive experience of the Nanoworld.
This is the world to be conquered in the 21st Century!
A nanometre is extremely tiny. There are a billion nanometres in one metre.
Your finger nail is about 10 million nanometres wide. A grain of sand is about 10 thousand nanometres wide. One of your hairs grows about 1 nanometre each second. The diameter of a large atom is about half a nanometre.
How do we explore the Nanoworld?
We cannot use our eyes to ‘see’ the nanoworld because visible light cannot image very small things. Instead scientists use several other techniques – come and discover some of them here.
We see when visible light enters our eyes. The wavelength of visible light is about 1000 times longer than an atom so it is impossible to use visible light to see an atom. That would be like feeling for a pea with a dumper truck! This means we cannot see atoms with our eyes. So, scientists have to find other means to explore the nanoworld of atoms and molecules.
A Model SPM: you can use it to make a ‘nanowire’
SPM stands for Scanning Probe Microscope.
The magnification produced by an SPM is so huge scientists can ‘see’ and move individual atoms with its probe.
An SPM is a microscope for ultra-high magnification. It uses an ultrafine ‘tip’ to scan over a surface and image individual atoms. However, this is not easy because atoms and molecules move continuously and randomly. At very cold temperatures (blue lights) it is possible to manipulate the particles to complete the wire. When the temperature increases (red lights) the atoms move violently and it is impossible to manipulate the atoms.
The model explains one way an SPM is used.
Computers could be made 1000 times faster and 1000 times smaller using nanowires
Natural forces bring atoms and molecules together to form amazing structures.
Atoms and molecules attract each other by the forces that exist between their electrons. This attraction leads to ‘Self-assembly’.
Can you see the different structures being assembled? Look out for: clusters | chains | rings | interlocked rings See how they form and break up!
The balance of attraction and repulsion between the electrons in different atoms determines the shapes and structures that are formed by self-assembly.The forces between atoms are continually disrupted by movement and vibration of atoms and molecules due to energy in the form of heat. This motion may appear to be a nuisance, but it is essential for allowing atoms to find their most stable bonding positions in a structure!
What can nanoscience do for us?
Being able to manipulate matter at the atomic level will revolutionise everything in our world - from healthcare to new energy sources.
New electronic devices: Ultra-small molecule-based electronics and computing devices; electronic paper; iPods with 1000s of GB capacity.
Biomedical: Tissue engineering using carbon nanotubes to act as scaffolds to grow artificial organs; Biocompatible implants; Wound-dressings using silver nanoparticles
Alternative energy: Capturing Solar energy; Vastly improved battery lifetimes; Hydrogen storage as new compact, lightweight fuel.
Smart (“chameleon”) materials: Change shape, colour, electrical conduction in response to stimulus.
The Nanoworld is never still!
All atoms vibrate continuously and randomly because they have heat energy - the hotter the temperature the more lively the movement.
Blue: At very, very cold temperatures, close to absolute zero, the atoms are almost still. (Absolute zero is 0 Kelvin = - 273 OC)
Pink: At room temperature, the atomic vibrations can be clearly seen.
Red: At high temperatures, the atoms vibrate violently. Melting occurs if the atoms break loose from the lattice structure.
Infra-red beams to probe the nanoworld.
The nano-world is full of Molecules. Molecules are very small - you can line up a million molecules in 1 millimetre! Molecules are made up of atoms with bonds between them. The bonds act as springs and can vibrate when infra-red light is shone on the molecule.
Molecules can vibrate in a number of ways e.g. by stretching and contracting their bonds (like a spring), or by changing angles between atoms (e.g. by bending, rocking, wagging or twisting). Each molecule has its own signature vibrations. These vibrations absorb specific wavelengths of infra-red light . When the beam reaches the detector, the light absorbed at different wavelengths can be measured and this information acts as a ‘fingerprint’ that scientists use to identify the molecule.
Below are the infrared absorption bands of Water and Carbon Dioxide
X-Rays can identify the atoms in the nanoworld.
We can use X-rays to identify which atoms are present in a material. The X-Ray beam excites the sample which emits electrons. The energy of the electrons identifies the type of atoms present in the sample.
The X-Ray beam is steered by mirrors to hit a sample in the investigation chamber. The atoms in the sample are excited and emit some of their electrons. Different elements emit electrons at different energies. The analyser is used to measure the number of electrons emitted at different energy values – this can be plotted to give Electron Energy Spectra, which are “fingerprints” of the elements in the sample.
Note: Air molecules can easily capture the emitted electrons. So, the air in the investigation chamber is pumped out to produce a vacuum comparable to that in space - this allows the emitted electrons to reach the analyser and be detected.
Teachers - Pupils - Parents
Are you planning to visit the Giants of the Infinitesimal Exhibition?
Information and activities are available here to download and print.
- Nanoscience education downloads:
- KS 4 and Advanced level: Detailed notes + questions and answers + curriculum links
- Download PDF
- KS3 and 2: Notes + activities + curriculum links
- Download PDF
Contact: firstname.lastname@example.org with queries
Education Consultant: Ann Marks MBE