In this project funded by the Chemical Structure, Dynamics & Mechanisms B Program of the Chemistry Division, Professor Lei Zhu of the Department of Chemistry and Biochemistry at Florida State University is developing new organic fluorescent molecules that are capable of emitting light of more than one hue (i.e., multiple emission) to produce composite colors. The project could lead to energy-efficient light-emitting materials. The research is unique as dialing up or down the electrical energy input to the device could lead to the production of different colors. This project lies at the interface of chemistry, materials, and physics and is therefore well suited to the education of well-informed scientists. Outreach activities include developing a course on the chemistry and physics of light that targets upper-class undergraduate students and early graduate students in STEM disciplines. The new course aims to enhance the students' understanding of light-involved science and technologies, which is and will be at the forefront of the efforts to improve the well-being, and satisfying the curiosity, of society with contributions to a vast range of areas from energy sectors to space exploration.
In more technical terms, this project aims to provide structural models to produce excitation-dependent dual-emitting fluorophores, including one class that has the potential to undergo thermally-activated delayed fluorescence (TADF). Beside fundamental molecular photophysics, the research program also includes technical innovation in characterizing the stability of organic emitters in an operating organic light-emitting diode (OLED). In the first objective, the structural factors that would provide a pathway of excitation-dependent dual emission will be identified. In the second objective, a new class of organic dyes that are easy to prepare will be studied with the focus on their potential for TADF. The ability of TADF may increase the electricity to photon conversion efficiency in an OLED, and is of intense commercial interests. The compounds that are both TADF-capable and bright will be evaluated as emitters in OLEDs. In the third objective, the excitation-dependent properties that are described in the first objective will be included in the TADF scaffolds from the second objective to offer bright, stable, and excitation-dependent TADF dyes capable of dual emission.
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.