CHEE Seminar: Biwu Ma
Monday, March 27, 2023 – 3:00 p.m.
Biwu Ma
Professor, Department of Chemistry and Biochemistry
Florida State University
“Low Dimensional Metal Halide Perovskites and Hybrids: From Synthetic Control to Device Integration”
Harvill Bldg., Room 302
Social Hour immediately follows the seminar in Old Engineering 157 (Graduate Student Lounge) at 4:00 p.m.
ABSTRACT
Metal halide perovskites and perovskite-related organic-inorganic hybrid materials have emerged as new generation functional materials with exceptional structure and property tunability for a wide range of applications, from photovoltaic cells (PVs) to light emitting diodes (LEDs), photodetectors, lasers, and radiation detectors. By controlling the morphological dimensionality of metal halide perovskites with ABX3 structure, low dimensional perovskites, including 2D nanoplatelets, 1D nanowires, and 0D quantum dots, have been developed to exhibit distinct properties from their 3D counterparts, as a result of quantum size effects. Besides 3D ABX3 perovskites, organic metal halide hybrids (OMHHs) with low dimensional structures at the molecular level can be prepared by using appropriate organics and metal halides, in which metal halide building blocks, for instance, metal halide octahedra, form 2D, 1D, and 0D structures that are completely isolated and surrounded by organic cations. These OMHHs exhibit unique properties that are different from those of 3D ABX3 perovskites. For instance, broadband white emissions have been shown in corrugated-2D and 1D OMHHs, and near-unity photoluminescence quantum efficiency (PLQE) has been achieved in 0D OMHHs with tunable emissions from blue to green, yellow, orange, and red. In this talk, I will present our recent efforts in the development and study of low-dimensional metal halide perovskites and hybrids, from synthetic control to device integration. The applications of these materials in optically pumped white LEDs, electroluminescent devices, afterglow, and X-Ray scintillators will be discussed.
BIOSKETCH
Dr. Biwu Ma is currently a professor in the Department of Chemistry and Biochemistry at Florida State University. He is also a faculty affiliated with the Materials Science and Engineering Program. Dr. Ma received his Ph.D. in materials science from the University of Southern California in 2006 with research work in OLEDs under the guidance of Professor Mark Thompson. He then performed postdoctoral research in plastic electronics with Professor Jean Fréchet at UC Berkeley and Lawrence Berkeley National Laboratory (LBNL) for 2.5 years, before becoming a staff scientist at the Molecular Foundry at LBNL. After 5 years of stay at the Molecular Foundry, Dr. Ma joined the faculty at Florida State University through the university’s energy and materials initiative in 2013. Dr. Ma’s current research focuses on the development of new functional materials with controlled chemical and physical properties for applications in a range of technological areas, from energy to environmental and information technologies. Of particular interest are light-emitting diodes, solar cells, photodetectors, and sensors. Dr. Ma has authored and co-authored more than 115 peer-reviewed publications with total citations of more than 15000 and an H-index of 58 as of today.