Title: Thermodynamic determination of biphasic nanoparticle geometry
Abstract: Bimetallic nanoparticles are a potential solution to studying the SERS spectra of molecules that do not bind will to traditional SERS substrates without needing a chemical linker. When the two metals are poorly miscible the resulting biphasic particle can adopt several geometries, including Core-Shell and Janus. The Janus type particles have great potential as SERS substrates, as one metal can be selected to bind the target molecule while the other metal provides the plasmonic enhancement. Some of the challenges of working with these systems are choosing a relative composition of the metals such that the final geometry is the desired Janus type, and determining whether the shape of the Janus particle allows for sufficient field enhancement on the non-plasmonic side. A thermodynamics model can be used to predict the geometry of the biphasic particle as a function of composition, and for the Janus type particles can be used to predict the shape of each phase and the interface.
Bio: Chelsea Mueller received her undergraduate degree in Chemistry in 2015 from the University of Wisconsin at Stevens Point. As a graduate student at Northwestern, she has worked on theory projects involving rotational alignment of open-shell diatomics, TERS imaging with semiempirical methods, and most recently using thermodynamics to predict the geometry of bimetallic nanoparticles in order to study their plasmonic properties. She is currently a fourth year PhD student in the Schatz group.