School of Chemistry Colloquium: Prof. Ashok K. Ganguli (Indian Institute of Technology Delhi) Design of functional nanostructures for photoelectrochemical and biomedical applications and layered materials for energy storage

We have been working in a variety of materials related to energy (Photoelectrochemical water splitting and battery electrodes) and upconverted nanoparticles for biomedical imaging and drug delivery. Designing semiconductor heterostructures to efficiently harness solar energy and utilize the charge carriers for visible-light photocatalysis and water splitting has been investigated in detail. Conjugation of CdS supraparticles with rGO (electron scavenger) / hole scavenger (cobalt phosphate (CoPi) provides slower carrier recombination rates and higher photoelectrochemical efficiency compared to bare CdS supraparticles and the excited states have been followed using ultrafast spectroscopy.
Upconversion materials have attracted considerable research interest for their application in bioimaging of cells, for near-Infrared activated photodynamic therapy and as nanoscintillators. Surface – modified spiky silica nanoparticles with MOFs like ZIF-8/ZIF-90 and rough MgO@SiO2 demonstrate high doxorubicin loading capacity and drug delivery. We investigated the performance of Na2Ti3O7 (NTO) as an active electrode material for lithium-ion batteries (LIB). We explored the incorporation of multi-walled carbon nanotubes (CNTs) as conductive additives along with carbon black (CB) to form a composite electrode. Furthermore, we have explored the dual behaviour of NTO as an anode material for both LIB and SIB (sodium-ion battery). Our findings revealed distinct redox mechanisms for the two systems. Additionally, we investigated Na3V2(PO4)3 (NVP), as an electrode material for sodium-ion batteries. Temperature-dependent studies revealed that NVP-A outperformed NVP-C under all conditions. Post-cycling investigations employing ToF-SIMS, XPS, and XANES provided crucial insights into the degradation mechanisms of NVP.

This event is open to final year undergraduate students, MSc students, PhD students, PDRAs and academic staff.