Feb 5 , Thursday: 4:15 p.m. / Rockefeller 301
Barry Rand , Princeton
Teaching old materials new tricks: Making organic semiconductors crystallize on demand and metals emit light
In this seminar, we will focus on two aspects of our work that look at materials which have been studied for quite some time, but try to utilize them in new and interesting ways. In the first part, we will focus on our recent efforts to template the growth of organic semiconductors. Through proper control of crystal phase, molecular orientation, and grain size (from nanometers to micrometers), we are able to realize higher solar cell performance from "classical" materials than otherwise possible. In the second part, we will look at metals, specifically Au and Ag. It turns out that metals, like semiconductors, can be quantized for diameters less than 2 nm. At such sizes in fact, even relatively efficient quantum yields of emission have been demonstrated. Here, we look at thin films of metal nanoclusters (MNCs), and demonstrate a thin film LED with either Au or Ag MNCs as the emitting element.
Host: Ken Singer