29 Nov '19
An international group of scientists led by researchers at Skoltech (Institute of Science and Technology on the premises of the Skolkovo innovation hub just outside Moscow) have developed a method that enables the fine-tuning of single-walled carbon nanotube (SWCNT) films’ optoelectrical properties by doping those with special alloying solutions.
The team tried to improve some of the key characteristics, including conductivity, a Fermi level and some others. According to Alexei Tsapenko, a Skoltech postgraduate, the current methods that exist for the doping of SWCNT films pose certain problems to researchers as spatial uniformity and easy scalability are hard to achieve.
Earlier this year the Skoltech-led group came up with a new method that is said to enable even and precise application of dopants to an unlimited number of nanotubes.
The researchers made a simple device that generated a jet stream consisting of microscopic alcohol droplets that contained gold salts and other compounds to be used as dopants. When directed to SWCNT films, compressed air blown through the device helped cover film surface with a dopant solution very uniformly.
When the droplets dried, the surface of the nanotubes had a layer of alloying elements with a clearly preset thickness. That resulted in the lowering of films’ electrical resistance by an impressive 25 times and an improvement of their semiconducting properties without compromising their transparency and other optical characteristics.
Mr. Tsapenko believes the same method can be used to treat other nanomaterials and also to embed in them nanoparticles of gold and other metals which could help vary material properties. The research is believed to step up the development of next gen computers, making them faster and less energy-consuming.