Collaborative Research: Diarylethene-based Crystalline Materials: Design and Function

University Of New Mexico, Albuquerque NM

Investigators

Abstract

Non-technical Abstract: In this project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, Associate Professor Jason Benedict of the University at Buffalo, The State University of New York and Professor Jeffrey Rack of the University of New Mexico are developing crystalline porous materials that are activated by UV light. These molecular materials comprise photo-active chemical groups that change shape when exposed to light. The light-driven molecular transformations cause the pores (holes) and channels in the crystals to change shape and dimension. This leads to the development of smart materials capable of selectively absorbing or releasing guest molecules, but only when exposed to the proper wavelength of light. Experiments using ultrafast pulses of light and/or X-rays reveal critical insights into the fundamental photochemistry that occurs in these novel materials. The research establishes much needed design principles to understand and enable the rational design of next-generation photo-responsive materials. The educational projects include the continuation of the U.S. Crystal Growing Competition, and a nation-wide crystal growing competition, that brings concepts of crystals and crystal growth into K-12 classrooms and home schools throughout the country by providing participants a fun and exciting hands-on STEM-based contest. Technical Abstract: Integrating the photo-responsive properties of diarylethenes into hybrid crystalline systems transforms these traditionally passive materials into active materials that change their chemical or electronic properties in response to light stimulus. The PIs' innovative approach - using ring-closed diarylethene building units - ensures the reliable and predictable synthesis of photo-responsive crystalline materials. Given the importance of extending longevity in sustainable materials development, the proposed research also includes an effort to identify and understand the root causes of fatigue in these systems. The photochemical reactions in these materials, both desired and undesired, are precisely monitored through advanced spectroscopic and in situ X-ray diffraction methods. These experiments provide a crucial link between the molecular photochemistry and the photophysics of the proposed hybrid crystalline solids. It is anticipated that the design principles and experimental techniques developed through this collaborative research program can be extended to other photochromic systems. The outreach efforts bring concepts of crystal growth classrooms across the country through the continued growth of the US Crystal Growing Competition. 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.