Barry P. Rand
Professor of Electrical and Computer Engineering
Andlinger Center for Energy and the Environment
Princeton University
Date: September 16, 2024
Time: 3:00 - 4:00 PM ET
Location: Building 34, Room 401 (Grier Room)
Reception to follow
Abstract
Metal halide perovskite semiconductors have captured significant interest in the thin film optoelectronics community. As one example, certified photovoltaic efficiencies of metal halide perovskite solar cells currently exceed 26%, making them competitive in the laboratory with well-established technologies like crystalline Si, CdTe, and CIGS. Also, recent gains have been made in perovskite-based light emitting devices (LEDs), with external quantum efficiency (EQE) beyond 25% realized for bromide (green) and iodide (red/near-infrared) based perovskite emission layers.
In order to better understand the physics of device operation as well as degradation, we need to understand what can occur at interfaces of halide perovskites with other materials. For example, we have determined that metal halide perovskites not only feature mixed ionic-electronic motion but are also considerably chemically reactive, for example via redox (electron transfer) or acid-base (proton transfer) reactions. We have found these processes responsible for metal contact and ITO corrosion/etching, for iodine transport into hole transport layers, for halide phase segregation, and even for Au transport. In addition, it may be possible to exploit this reactivity to allow for doping, with important implications on perovskite optoelectronic devices.
Biography
Barry Rand earned a BE in electrical engineering from The Cooper Union in 2001. Then he received MA and PhD degrees in electrical engineering from Princeton University, in 2003 and 2007, respectively. From 2007 to 2013, he was at Imec in Leuven, Belgium, ultimately as a principal scientist, researching the understanding, optimization, and manufacturability of thin-film solar cells. Since 2013, he is jointly appointed between the Department of Electrical and Computer Engineering and Andlinger Center for Energy and the Environment at Princeton University.
Prof. Rand’s research interests highlight the border between electrical engineering, materials science, chemistry, and applied physics, covering electronic and optoelectronic thin-films and devices. He has authored approximately 200 refereed journal publications, holds 25 US patents, and has received the 3M Nontenured Faculty Award (2014), DuPont Young Professor Award (2015), DARPA Young Faculty Award (2015), ONR Young Investigator Program Award (2016), and Gordon and Betty Moore Foundation Experimental Physics Investigators Initiative Award (2023).