CAS:Rigidochromism in Polynuclear Metal-azole Macrocycles and Networks

Purdue University, West Lafayette IN

Investigators

Abstract

With support from the Chemical Structure, Dynamics and Mechanisms Program B, Professor Alexander Wei at Purdue University will develop new luminescent (light-emitting) molecules. Advances in organic light-emitting devices (OLEDs) depend on chemically stable materials that emit at red, green and especially blue wavelengths. This research focuses on the synthesis and luminescent properties of rigid, saddle-shaped molecules which are held together with copper ions. One important question is why these molecules are rigid. Some of these light-emitting copper complexes can also switch colors in response to changes in their environment and may beapplied as chemical sensors. Grant activities are aimed at understanding the relationships between molecular structure and photophysical properties. This research has the potential to facilitate advances in the design of flexible solid-state lighting and displays through innovative experiments that can convey these relationships to students and the general public. Research activities in this project will include: (i) correlating azole structure with rigidochromic behavior of the corresponding copper complexes; (ii) developing orthogonal approaches for tuning molecular energy band levels of solid-state emitters; (iii) designing metal‒organic frameworks (MOFs) that align excited-state dipoles for uniaxial emission. All objectives have important ramifications for the design of emissive materials with potential applications in the development of efficient OLEDs. These objectives are rooted in fundamental materials research based on the principles of supramolecular chemistry. In addition, these colorful complexes offer educational opportunities to demonstrate important chemical concepts to students and the public at large. As part of a K-12 outreach activity in association with the Purdue Department of Chemistry, Professor Wei and his team will design luminescent test strips that can produce green light when heated, and blue light when exposed to volatile hydrocarbons such as gasoline vapor. 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.