Hexacoordinate Silicon Complexes for Electronic Devices

University Of North Carolina At Charlotte, Charlotte NC

Investigators

Abstract

The Chemical Synthesis Program of the Chemistry Division supports an interdisciplinary research team led by Professors Thomas A. Schmedake (Dept. of Chemistry), Michael Walter (Chemistry), and Yong Zhang (Electrical and Computer Engineering) at the University of North Carolina - Charlotte to develop hexacoordinate silicon complexes for optoelectronic device applications like the development of photovoltaics for harvesting light energy or fiber optic communications. The goal of the project is to overcome some of the current limitations of organic electronic devices by developing new silicon-based molecular materials with electronic and optical properties superior to those of current materials. To accomplish this goal, the team at UNC Charlotte is developing new methodology for synthesizing chemically stable and robust silicon complexes with optimized electronic and optical molecular properties. Once made, the complexes are incorporated into prototype devices to measure their effect on device performance. This interplay between the synthesis of the complexes and device fabrication serves to elucidate the molecular-level synthetic design principles needed for macroscale device optimization. The interdisciplinary project spans the fields of chemistry, materials science, and electrical engineering and provides exceptional training for students at various stages in their careers ranging from high school through graduate school. In addition, the collaborators work with a local science museum, teachers, and schools to develop and provide outreach programs in chemistry and STEM. The team at UNC Charlotte is synthesizing new electron transport layer and electroluminescent materials based on neutral hexacoordinate silicon complexes with dianionic pincer ligands for added chemical stability, robust redox chemistry, low dipole moments, simple stereochemistry, and low reorganization energies. These are ideal properties for molecular components in organic light emitting diodes, phosphorescent LEDs and other molecular electronics devices. The complexes are also attractive candidates for vacuum deposited, high-efficiency, and earth-abundant replacements of rare-earth element phosphor coatings for inorganic LEDs. The program involves both the development of the synthetic complexes and their incorporation into prototype devices so that their properties can be measured. These research components are being integrated with both the classroom teaching of the investigators and ongoing collaborations with a local science museum, teachers, and schools to develop and provide outreach programs in chemistry and STEM. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.