Metal Nanoparticle Array Formation by Pulsed Laser-induced Thin Film Dewetting and Their Applications ；
Metal Nanoparticle Array Formation by Pulsed Laser-induced Thin Film Dewetting and Their Applications
Department of Chemistry, University of Calgary, Calgary, Alberta, Canada
Ordered arrays of metal nanoparticles (NPs) have found many applications, for example, as catalyst arrays for the growth of semiconductor nanowires/carbon nanotubes and as model electrodes for electrocatalyst evaluation in fuel cells. Compared to wet chemical methods and lithography-based nanopatterning, pulsed laser-induced dewetting (PLiD) is a versatile, simple, and high throughput method for the synthesis of metallic NPs of controlled size and shape. In this talk, I will present our recent work on the formation of Au, Pt, and Ag NPs via PLiD of single-layer metallic thin films and the fabrication of bimetallic NPs from PLiD of bilayer thin films. Our work has showns that PLiD can be used to produced NPs of both low-melting-point and high-melting-point metals, providing a powerful alternative to thermal dewetting. In addition, quantitative evidence has been provided to show that PLiD of Au and Pt follows spinodal dewetting mechanism. Pt@Au bimetallic NPs can be produced via PLiD of bilayer thin films, independent of the sputtering sequence. The application of the Au NPs as catalysts in silicon nanowire growth in a chemical vapor deposition process will also be presented.
Bio – Yujun Shi
Dr. Yujun Shi is a Professor in the Department of Chemistry at the University of Calgary in Canada. She received her BSc/MSc in Chemistry in 1988/1991 from SoochowUniversity in China, her PhD in Chemistry in 2001 from the University of Western Ontario (now WesternUniversity) in Canada. She did her postdoctoral work in the Steacie Institute for Molecular Sciences at the National Research Council of Canada with an NSERC Visiting Fellowship. In 2003, Dr. Shi started her independent career as an Assistant Professor in the Department of Chemistry at the University of Calgary. Her group’s research focuses on application of laser dewetting methods for metal nanoparticle formation, development of laser analytical techniques, and understanding the chemical vapor deposition at a molecular level. Her research has been published in peer-reviewed journals, including Acc Chem Res, Adv Mater and Adv Funct Mater. She has served the role of the Associate Editor of Canadian Journal of Chemistry since 2012.