Size doesn’t matter, right? ☹ A quote that all men live by, but in the case of nanotechnology and the physical properties of particles, size does matter. In fact, when particles are created within 1-100 nanometers, the properties of these materials change significantly. Ever heard of the word quantum? Well, this is where quantum effects, which essentially are just phenomena that cannot be fully explained by classical mechanics, control the properties of particles. At the nanoscale, properties such as melting point, fluorescence, electrical conductivity, magnetic permeability, and chemical reactivity change.
A great example used by nano.gov involves nanoscale gold. Regular gold, as we all know, is yellow or gold, in color, but alternatively, nanoscale gold appears red or purple. This is because the gold’s electrons are more confined when is it at the nanoscale and due to this restriction, the nanoparticles react differently with light thus producing a different color. Scientists are able to take advantage of this ability for particles to obtain varying properties and apply them to research in many disciplines.
But there are even more properties of particles at the nanoscale. Essentially, nanoparticles have a much larger surface area than regular particles, which is difficult to wrap your brain around since they are much much smaller. For a strong explanation of this phenomenon please click here. But because of this increased surface area, nanoparticles gain an improvement in reactivity. This makes them act as better catalysts and are often used in the oil and chemical industries.
The last nano property, that you may have already heard of, is quantum tunneling. In essence, quantum tunneling is a micro nanoscopic phenomenon where a particle violates the principles of classical mechanics by penetrating a potential barrier higher than the kinetic energy of the particle. For more information on tunneling please click here. The main applications of quantum tunneling are resonant tunneling diodes, which are used to switch units in fast electronic circuits which can lead to flash memory for computing, and for the Scanning Tunneling Microscope, which allows for accurate mapping of a surface, atom by atom.
So yes, unfortunately for men, size does matter sometimes, but especially when it comes down to the nanoscale. Researchers and scientists are able to take advantage of these quirky and unique properties in order to improve science for the future.