Carbon nanotubes have remarkable intrinsic mechanical and transport properties compared to conventional fibre materials. They demonstrate a unique combination of extremely high stiffness, strength and tenacity combined with high levels of thermal and electrical conductivity. The structure of a nanotube strongly affects its electrical properties and depending on the chirality, carbon nanotubes can act as a conductors or a semiconductors. The above properties can be utilized to produce electricity generating devices. There are various methods of direct transformation of other forms of energy into electrical energy. Our group is currently exploring electromagnetic induction, electro chemistry, photoelectric, thermoelectric and piezoelectric effects and radio electricity.
Carbon nanotubes can be used to make piezoelectric energy harvesting devices which convert mechanical stress into electricity. Carbon nanotubes make the device strong, flexible and light weight. For example, if we incorporate this device into a pair of jogging shoes, the mechanical stress applied during running can be used to generate electricity.
The semiconducting nature of carbon nanotubes can be utilised to generate electricity directly from radiation produced by radioisotopes and in particular beta emitting radioisotopes are suitable for generating radio electricity. A radioelectric device made from CNTs would be cheap, light, strong and durable and can generate electricity for a long time, possibly even hundreds of years, due to the long half-life of radioisotopes. For example, a radioelectric device made from CNTs could be used to make a cardiac pacemaker more durable and with longer service life than a traditional chemical battery which requires replacing.
Another way of generating electricity may be via the use of thermoelectric effect. This effect refers to the direct conversion of temperature differences to electric voltage and vice versa. By studying this behaviour with carbon nanomaterials we are able to build efficient thermoelectric devices.