‘Chemical’ Field and Multielement Nanoparticle Tectonics
Abstract:
I believe that a vast structural library of nanoparticles can be prepared by re-conceptualizing multicomponent nanoparticles as nodes from which many new structures can be prepared. If one views a multielement nanoparticle as a collection of numerous smaller building blocks, which can be converted compositionally, the possibility of explosive growth of chemical library can be envisioned. By eliciting conditions to partially fluidize and move atoms between these small building blocks in a regiospecific manner, new materials phases and interesting heterostructures can emerge.
The energy of atoms in nanoparticles is dependent on the coordination number of atoms or attached molecules and the distance from a high-energy surface or interface. The energy gradients in a nanocrystal, caused by various factors of chemical nature such as bonding or coordination number, were named as ‘Chemical Fields’; the energy level of an atom or ion is defined by its chemical state, and is attenuated at long distance from the high energy point, similar to ‘magnetic or electric fields’. I have hypothesized that by directing the movement of atoms using such energy gradients within the nanoparticle, we can easily transform them into various metastable states, which in turn would lead to myriads of new structures.
In this seminar, I will present our recent efforts in synthesizing new nanostructures by applying the concept of chemical field. New synthetic pathways, aided by understanding of ‘chemical field’, might make numerous exciting nanostructures visible, thus unleashing great application potentials of them in future technologies.