Stretchable Tb-Tb Distance Regulates the Piezofluorochromic Behavior of Chiral Tb(III)-MOF upon Compression

Ziyou Zhang; Dongping Deng; Xiaoqian Xu; Jiangwei Zhang; Shuai Yan; Zhiying Guo; Hongliang Dong; Zhiqiang Chen; Zhi Su

doi:10.1021/jacsau.4c00259

Stretchable Tb-Tb Distance Regulates the Piezofluorochromic Behavior of Chiral Tb(III)-MOF upon Compression

JACS Au. 2024 May 11;4(5):2050-2057. doi: 10.1021/jacsau.4c00259. eCollection 2024 May 27.

Authors

Ziyou Zhang^{1

2}, Dongping Deng¹, Xiaoqian Xu¹, Jiangwei Zhang³, Shuai Yan⁴, Zhiying Guo⁵, Hongliang Dong², Zhiqiang Chen², Zhi Su¹

Affiliations

¹ Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210046, China.
² Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China.
³ College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, China.
⁴ Shanghai Synchrotron Radiation Facility, Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China.
⁵ Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.

Abstract

Luminescent chiral Tb-MOF microcrystals with the Tb₂(COO)₄ subunit indicated strong green mechano-luminescence under compression. Furthermore, piezofluorochromic behavior in the diamond anvil cell was observed, with the intensity tendency of decreasing-increasing-decreasing and a shortened lifetime upon compression, due to the reversible stretchable Tb-Tb interactions. The Tb-Tb distance upon compression was refined through in situ high-pressure X-ray absorption spectra, which was consistent with the tendency of the piezofluorochromic intensity. In situ high-pressure UV-vis absorption spectra, Fourier transform infrared spectra, and powder X-ray diffraction demonstrated the full recovery of Tb-MOF after over 10 GPa compressions due to the semiflexible ligand. This work not only provided an ultrastable Tb-MOF but also illustrated the relationship of the piezofluorochromic behavior with the detailed structural transformation for the first time.