Research Projects

Nanoscale chirality has emerged as a frontier topic of research over the last decade with significant implications in the field of optoelectronic devices, optical sensing, catalysis, and enantioselective separations. While plasmonic nanostructures of gold and silver exhibit exceptional electromagnetic properties, the emergence of intrinsic chirality in such systems, particularly without the use of any chiral templates, remains highly challenging. One of the major objectives of the project is to investigate novel synthetic strategies for producing intrinsically chiral plasmonic nanostructures by employing a diverse set of chiral reagents, and to uncover the mechanisms underlying the development of nanoscale optical activity. The central hypothesis of the proposed research is that the selective binding and directional influence of chiral molecules during the atom deposition stages governs the anisotropic growth of metal nanostructures, leading to chiral geometries with distinct chiroptical responses. The project will explore how facet-selective growth, mediated by chiral ligands or surfactants, can break spatial symmetry during nucleation and growth. This is expected to result in nanoscale architectures that display measurable chiroptical signals, major being circular dichroism signals. With an aim to test the proposed hypothesis, the project will involve the controlled synthesis of metal nanostructures, primarily based on gold, silver, and copper, using three class of chiral reagents which includes (i) point chiral molecules, (ii) axial chiral compounds, and (iii) chiral surfactants. Growth dynamics and structural evolution will be characterized using high-resolution electron microscopy, 3D TEM tomography, UV-Vis-NIR spectroscopy, and circular dichroism spectroscopy. Theoretical simulations will be adopted to further strengthen the understanding on the mechanism of chiral growth. A systematic variation of synthetic parameters will allow the establishment of structure–property correlations between particle morphology and their chiroptical response. In addition to exploring the fundamentals of chiral growth, the project aims at finding potential applications for the synthesized chiral nanoparticles. In the application phase, the project will utilize these chiral nanostructures as substrates in Surface-Enhanced Raman Scattering (SERS) to detect enantiomerically pure or enriched analytes of chemical and biological relevance. Additionally, their catalytic performance will be evaluated in model asymmetric transformations to assess their efficacy in enantioselective catalysis. By combining the hypothesis-driven synthesis with structure–function analysis and proof-of-concept applications, this work is expected to provide critical insights into the origin of chirality in nanomaterials in general, and plasmonic nanostructures in particular. The outcome will not only advance fundamental understanding in nanomaterial chirality but also open up transformative opportunities for real-world applications in chemical sensing, biosensing, and asymmetric synthesis.