Synthesis of Hierarchical Materials with a Tunable Photoisomerization Response

Non-technical Summary:

With this project, supported by the Solid State and Materials Chemistry Program in the Division of Materials Research, principal investigator (PI) Prof. Natalia Shustova and her research group at the University of South Carolina at Columbia develop crystalline metal-organic framework (MOF) materials for which electronic properties can be modulated through external stimuli, such as light or heat.

They also study the fundamental understanding of these materials which elucidates the concept of tailoring material properties upon light irradiation. This in turn advances applications ranging from adaptive lenses and memory storage devices to nonlinear optics, fuel cells, or field-effect transistors. A specific example is that the proposed crystalline photoresponsive materials enable future optoelectronic materials.

The research is synergistic with the Materials Assembly and Design Excellence in South Carolina (MADE in SC). In addition to transformative research, PI Shustova also continues the development of the Carolinian Women in Science (Wi-Sci) Supportive Network. The major Wi-Sci goal is to create and grow a network of support for women currently at the Carolinian institutions of higher education, including historically black colleges and universities (HBCUs), and therefore increase opportunities for women to attain at least 50% of the positions projected for STEM disciplines in the Carolinas.

The proposed Wi-Sci initiative integrates educational and research opportunities for female students in STEM disciplines. Technical Summary:

Achieving control over photoisomerization kinetics through material design is a challenge that must be addressed to advance the fields of optoelectronics or memory and energy storage. However, fundamental principles, that allow for enabling control over photoisomerization kinetics (i.e., achieve reversible and fast material photoresponse) are still vastly underdeveloped.

This project, supported by the Solid State and Materials Chemistry Program in the Division of Materials Research, furthers the development of crystalline stimuli-responsive hybrid materials exhibiting tunable and reversible photoisomerization of coordinatively-immobilized stimuli-responsive units as a function of material topology. The research team pursues two routes to assemble photoresponsive MOFs: a) assembly of MOFs from a combination of photochromic ligands, such as diarylethene-based ones, and non-photochromic ligands; and b) photoisomerization through MOF-linker side groups.

Extensive photophysical analysis of the resulting photoresponsive frameworks are elucidating structure-property relationships related to electronic structure modulation. Additionally, the project promotes integration of educational and research opportunities for high school, undergraduate, and graduate students, with a special emphasis on women in STEM disciplines.

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.