Research Projects

This project aims to synthesize new metal nanoclusters (MNCs) using redox-active and ambiphilic ligands, which are expected to induce unique reactivity on the clusters. With ever-increasing demands and fast depletion of traditional energy source, it has become imperative to develop highly efficient catalysts for the chemical synthesis and energy conversion. In this regard, MNCs have been identified a potential candidate for the next generation catalytic system due to its small size and atom precise well-defined structure. In recent years, several metal nanoclusters of Au, Ag, and Cu have been synthesized using thiolate and phosphine-based ligands. However, their catalytic reactions for organic transformation are very narrow due to its limited activity and lack of mechanistic understanding. Hence, rational design and selection of proposed redox-active and ambiphilic ligands are anticipated to modulate the electronic and structural characteristics of the nanoclusters and enable them for multielectron/proton transfer reactions. While these ligands, often act as electron reservoirs by storing or releasing electrons and activate metal in molecular complexes, have shown great potential in small molecule activation, have yet to be explored in metal nanomaterials. To achieve the objectives of the proposal, a detailed research plan has been developed, which includes the synthesis of ligands and the use of size-focused and size-transformation methods to obtain new clusters of Au, Ag, Cu, and Ni. Our effort would be extended to develop high yielding synthetic protocols by screening various parameters such as ligand-to-metal ratio, type of reducing agents, reducing equivalent, temperature, time etc. Further, newly synthesized metal-nano lusters will be tested and evaluated for chemical reactions such as, hydroamination, C-H hydroxylation, nitrene transfer, small molecule activation (CO2 reduction, Nitrite reduction, H2 production). A detailed mechanistic understanding of this process will facilitate the development of catalytic systems for key reactions. In order to lead this project, principal investigator (PI) has displayed his ability and expertise in the field by making a new Au6 cluster with stibine ligand (ambiphilic).