Thermal and electrical conductivity of size-tuned bismuth telluride nanoparticles

A study was conducted to demonstrate the solution phase synthesis and characterization of thermal and electrical conductivity of size-tuned thiol-capped bismuth telluride single crystal nanoparticles. The chain length of the capping alkane thiol and reaction temperature were used to control the size of the resulting nanostructures. The investigations revealed that it was possible to anneal the particles to drive off the capping agent, while maintaining phase purity, pressing them into pellets, and improving the electrical transport properties. The carrier concentration was determined for the first time for chemically synthesized bismuth telluride nanostructures through Hall effect measurements. It was observed that annealing significantly improved the thermoelectric properties, which were most suitable for the samples prepared with the smallest particle sizes.