After his PhD in chemistry, obtained from the Indian Institute of Technology in Kharagpur, he had worked as a postdoctoral fellow at the University of South Carolina-Columbia and Clarkson University, USA, and as an assistant professor at the Panjab University in Chandigarh, India. From 2007 to 2009 he was an Alexander-von-Humboldt Research Fellow at the Ludwig-Maximilians-Universität, München, Germany. His research interests are in synthesis, spectroscopy and applications of colloidal metal nanocrystals. He has authored over 50 publications including patents and book chapters.