Date/Time: April 20, 2023 starting at 11:30 a.m.
Location: A.W. Smith Building, Room 349
Name of Speaker: Carlos A. Silvera Batista
Title: Long-range Transport and Interactions of Charged Colloids under Aperiodic Electrodiffusiophoresis
University: Vanderbilt University
Abstract: Colloidal materials display impressive features such as dynamic assembly and self-propulsion. These features are promising for achieving advanced materials that mimic the versatility of natural systems. Although electric fields are widely used to tune the transport and interparticle interactions of colloidal materials, dynamics is rarely studied under coupled gradients in electrical potential, and concentration of electroactive species (electrodiffusiophoresis). Therefore, electrodiffusiophoresis (EDP) remains a vastly underutilized mode of transport, in areas such as reconfigurable assembly, microfluidics and actuation of soft materials. In this work, we aim to uncover the physics governing the individual and collective dynamics of charged colloids under coupled gradients of electrical and chemical potentials. To enable these studies, we developed a method to simultaneously visualize the progression of concentration polarization and the ensuing dynamics of charged colloids near electrodes using confocal microscopy. The research approach consists in the study of pairwise interactions, the study of collective dynamics under complex concentration profiles, and transport analysis. The results from this research effort, not only have significant implications for the fundamental understanding of ac colloidal electrokinetics, but also provide new possibilities for the manipulation and directed assembly of charged colloids, such as the manipulation of nanoscale objects and their analysis at femtomolar concentrations.
Bio: Dr. Carlos A. Silvera Batista initiated undergraduate studies in chemical engineering at the Universidad de San Buenaventura (Cartagena, Colombia) and subsequently obtained a bachelor’s degree from the City College of New York (CCNY). Dr. Silvera began his research trajectory as a LSAMP scholar under the guidance of Prof. Ilona Kretzschmar (CCNY). After earning a PhD in chemical engineering from the University of Florida, Dr. Silvera held postdoctoral positions at the National Institute of Standards and Technology and at the University of Michigan, where he received the President’s Postdoctoral Fellowship. Currently, as an assistant professor at Vanderbilt University, his research interest is on the electrokinetics and directed assembly of colloidal systems. His research work has resulted in over 20 peer-reviewed publications in high-impact scientific journals, such as JACS, ACS Nano, Langmuir and Science. Recently, in 2023, Dr. Silvera was awarded the NSF CAREER Award. During his spare time, Dr. Silvera enjoys watching basketball, gardening, and the cooking of BBQ recipes from all over the world.