Perovskites with Precision: From Robots to Synchrotrons in the Quest for Robust Phase Stability

Abstract: The outstanding optoelectronic properties of halide perovskites position them as candidate materials for solar cells, displays, and more. Their compositional and process flexibility provides a broad and attractive design space of materials chemistry and has led to exceptional optoelectronic figures of merit. However, the same flexibility also gives rise to challenges in reproducible synthesis and phase instability. I will share our recent efforts to automate perovskite synthesis in the research environment to achieve improved synthetic control and accelerate the development of perovskite materials and devices with robust operational stability. Automation radically reduces operator- and process-induced variation and helps to reveal the underlying landscape of the materials chemistry. In addition, the ease of data collection in automated synthesis opens the door to data-driven optimization of functional properties and construction of predictive models based on the intersection of composition and process. We complement automated synthesis with X-ray nanoprobe characterization to dive into mechanisms of stability and performance improvement in frontier perovskite materials. Addressing the root causes of instability and process sensitivity will be critical to push perovskites to their fundamental material limits and harness their favorable properties for technological relevance at scale. 

Bio: David P. Fenning is the Francine Berman Professor in the Aiiso Yufeng Li Family Department of Chemical and Nano Engineering at UC San Diego. His group focuses on understanding defects and degradation reactions in energy conversion materials and devices, often working at the frontiers of synchrotron X-ray microscopy. Currently, his research involves the study of durability in high-efficiency silicon and perovskite photovoltaics and tandems, fundamentals of small molecule electrolysis, and phosphide photoelectrochemistry. He completed his Ph.D. at MIT in 2013 and then joined PV startup 1366 Technologies Inc. (now Cubic PV). After a postdoctoral fellowship at MIT, he joined the NanoEngineering department at UC San Diego in 2015.

Host: Plamen Atanassov