Grace Han

Grace HanAssistant Professor of Chemistry
Landsman Career Development Chair in the Sciences

Group website


Massachusetts Institute of Technology, Postdoc
Massachusetts Institute of Technology, PhD
POSTECH, Pohang, South Korea, BS


The major goal of my research program is to develop functional organic material systems that exhibit phase transitions, solubility changes, and nanoscale mechanical changes, triggered by external stimuli, notably light. These photo-controlled materials have a game-changing potential in waste heat recycling, solar energy conversion and storage, recyclable catalysis, single-molecule sensing, and reversible nanomaterial assembly. Since the photo-isomerization of switches has been traditionally studied in dilute solution, there exists a critical need to unravel this process in a crowded environment of condensed liquid or solid for successful applications. My group focuses on designing photoswitches with controllable structural parameters that determine their conformational freedom, photon absorption, and isomeric stability in condensed phases to yield deeper understanding of molecular switching dynamics in such environments.

Research image for Grace Han group

Selected Publications

  • S. Cho, J. Usuba, S. Chakraborty, X. Li, and G. G. D. Han* “Solid-State Photon Energy Storage via Reversible [2+2] Cycloaddition of Donor-Acceptor Styrylpyrylium System” Chem20239, 3159–3171.
  • X. Li, S. Cho, J. Wan, and G. G. D. Han*“Photoswitches and Photochemical Reactions for Optically Controlled Phase Transition and Energy Storage" Chem, 2023, 9, 2378–2389.
  • Q. Qiu, Z. Sun, D. Joubran, X. Li, J. Wan, K. Schmidt-Rohr, and G. G. D. Han* “Optically-controlled Recovery and Recycling of Homogeneous Organocatalysts Enabled by Photoswitches” Angew. Chem., Int. Ed. 2023, 62, e202300723.
  • Q. Qiu, Q. Qi, J. Usuba, K. Lee, I. Aprahamian*, and G. G. D. Han* “Visible Light Activated Energy Storage in Solid-State Azo-BF2 Switches” Chem. Sci.202314, 11359–11364.
  • A. Gonzalez, M. Odaybat, M. Le, J. L. Greenfield, A. J. P. White, X. Li, M. J. Fuchter*, and G. G. D. Han* "Photo-Controlled Energy Storage in Azobispyrazoles with Exceptionally Large Light Penetration Depths."  J. Am. Chem. Soc. 2022144, 19430–19436.
  • Q. Qiu, S. Yang, M. A. Gerkman, H. Fu, I. Aprahamian*, and G. G. D. Han* “Photon Energy Storage in Strained Cyclic Hydrazones: New Molecular Solar Thermal Energy Storage Compounds.” J. Am. Chem. Soc. 2022144, 12627–12631
  • M. A. Gerkman and G. G. D. Han* “Toward Controlled Thermal Energy Storage and Release in Organic Phase Change Materials.” Joule 2020, 4, 1621–1625.
  • M. A. Gerkman, R. S. L. Gibson, J. Calbo, Y. Shi, M. J. Fuchter*, and G. G. D. Han* “Arylazopyrazoles for Long-Term Thermal Energy Storage and Optically-Triggered Heat Release below 0 °C.” J. Am. Chem. Soc. 2020142, 8688–8695