METHOD FOR CONTROL OF SHAPE AND SIZE OF PB-CHALCOGENIDE NANOPARTICLES

Disclosed is a method for producing, controlling the shape and size oft Pb-chalcogenide nanoparticles. The method includes preparing a Pb (Pb) precursor containing Pb and a carboxylic acid dissolved in a hydrocarbon solution and preparing a chalcogen element precursor containing a chalcogen element dissolved in a hydrocarbon solution. The amount of Pb and chalcogen in the respective precursor affords for a predetermined Pb:chalcogen element ratio to be present when the Pb precursor is mixed with the chalcogen element precursor. The Pb precursor is mixed with the chalcogen element precursor to form a Pb-chalcogen mixture in such a manner that Pb-chalcogenide nanoparticle nucleation does not occur. A nucleation and growth solution containing a surfactant is also prepared by heating the solution to a nucleation temperature sufficient to nucleate nanoparticles when the Pb-chalcogen element mixture is added. Upon injection of the Pb-chalcogen element mixture into the heated nucleation and growth solution, Pb-chalcogenide nanoparticles nucleate and a Pb-chalcogenide nanoparticle solution is formed, which is thereafter cooled to a growth temperature that is below the nucleation temperature. The Pb-chalcogenide nanoparticle solution at the growth temperature is held at the growth temperature for a predetermined time period such that a desired nanoparticle size is obtained. The Pb:chalcogen element ratio and a surfactant in the nucleation and growth solution can control the shape of the Pb-chalcogenide nanoparticles. The nucleation temperature, the growth temperature, the time at which the Pb-chalcogenide nanoparticle solution is held at the growth temperature and a surfactant can control the size of the Pb-chalcogenide nanoparticles.