Title :

Solvated Metal Atom Dispersion and Digestive Ripening – Duo par excellence for Diverse Nanostructured Materials

Abstract :

The properties of nanostructured materials strongly depend on their size, shape, interparticle distance, and the surrounding environment which could be tuned precisely by controlling the particle size of the material. Size dependent property of a polydisperse sample is an average effect due to the presence of different sized particles in the system. The property exhibited by a monodisperse sample however, could be ascribed as emerging from a single entity. Control over size and size distribution is indispensible for attaining a desired property. A lot of attention is focused on developing synthetic strategies leading to monodispersity and those that are simple to manipulate, easy to scale up and highly reproducible.

We have been using the Solvated Metal Atom Dispersion (SMAD) method for the synthesis of colloids of metal nanoparticles. The as-prepared colloid from this method consists of polydisperse metal nanoparticles. In a process termed as digestive ripening, addition of a surfactant to the as-prepared sample renders it highly monodisperse. This combination, SMAD and digestive ripening has recently been extended to obtain nearly monodisperse semi-conductor nanostructured materials as well. In this talk, the power of the SMAD and the (co)digestive ripening processes will be demonstrated toward the synthesis of highly monodisperse metal, core-shell, alloy, intermetallic, and composite nanostructured materials. Additionally, applications of some of the materials synthesized using this methodology in the fields of hydrogen storage and generation, magnetism, catalysis, and surface enhanced Raman scattering will also be discussed.