04/19/2022
By Joanne Gagnon-Ketchen

Physics colloquium will be held on Wednesday, April 20, 2022 from 4 to 5 p.m.

This colloquium will be virtual. Contact Joanne Gagnon-Ketchen for link to join colloquium.

Dr. Michael B. Ross, Assistant Professor, Department of Chemistry, University of Massachusetts Lowell will give a talk on "Manipulating Plasmonics Using Post-Transition Metals."

Abstract: The design of new plasmonic materials is essential for continued progress in light manipulation at nanometer length scales. Often, multimetallic nanoparticles exhibit superior catalytic, mechanical, or corrosion-resistant behavior compared to their unary constituent counterparts. Despite these advantages, designing multimetallic plasmonic materials remains challenging because, except for Au, Ag, and Al, most metallic elements exhibit poor plasmonic behavior. This talk describes a strategy for manipulating the plasmon resonances of noble metal nanoparticles by post-transition metal alloying. It will discuss how the metallic properties of post-transition metals can be imparted onto the noble metals, enabling tunable higher energy plasmonic resonance that maintain high extinction coefficients and can penetrate into the ultraviolet. Importantly, theoretical analysis suggests that post-transition metal alloying with Bi, Ga, and In could enable analogous tunable plasmon resonances. Consequently, post-transition metal alloying can provide a general strategy for realizing a new and diverse class of tunable plasmonic materials.

Bio: Michael Ross is an Assistant Professor in the Chemistry Department at University of Massachusetts Lowell. His research interests focus on understanding the unique optical, chemical, and catalytic properties of metallic nanomaterials, and leveraging those properties to address challenges in energy, environmental detection, and photonics. In particular, these efforts have focused on using renewable electricity to generate hydrogen and fuels from water and CO2. Before that, he was awarded a CIFAR Bio-Inspired Solar Energy Postdoctoral Fellowship to study with Peidong Yang at University of California, Berkeley. There he investigated the properties of electrocatalysts that recycle carbon dioxide into fuels and chemicals. Michael earned his Ph.D. at Northwestern University as a National Defense Science and Engineering (NDSEG) Fellow. At Northwestern, under the guidance of Chad Mirkin and George Schatz, he focused on the design of optical properties in nanoparticle systems whose structure was programmed by DNA. He earned his B.S. in biochemistry at Providence College.