Journal
CHEMISTRY-A EUROPEAN JOURNAL
Volume 27, Issue 18, Pages 5632-5637Publisher
WILEY-V C H VERLAG GMBH
DOI: 10.1002/chem.202005362
Keywords
cationic metal– organic frameworks; environmental chemistry; fluorescent recognition; pertechnetate; pyrimidine
Categories
Funding
- National Natural Science Foundation of China [21876124, 21906116]
- Natural Science Foundation of Zhejiang Province [LR21B060001, LQ21B070004]
Ask authors/readers for more resources
A new water-stable cationic metal-organic framework ZJU-X8 was reported for efficient and selective detection of TcO4-, exhibiting a unique fluorescent recognition mechanism. Batch sorption experiments and DFT calculations demonstrated that only TcO4- could enter the framework through anion exchange, leading to a red-shift in the fluorescent spectra after interaction with silver ions.
As one of most problematic radionuclides, technetium-99, mainly in the form of anionic pertechnetate (TcO4-), exhibits high environmental mobility, long half-life, and radioactive hazard. Due to low charge density and high hydrophobicity for this tetrahedral anion, it is extremely difficult to recognize it in water. Seeking efficient and selective recognition method for TcO4- is still a big challenge. Herein, a new water-stable cationic metal-organic framework (ZJU-X8) was reported, bearing tetraphenylethylene pyrimidine-based aggregation-induced emission (AIE) ligands and attainable silver sites for TcO4- detection. ZJU-X8 underwent an obvious spectroscopic change from brilliant blue to flavovirens and exhibited splendid selectivity towards TcO4-. This uncommon fluorescent recognition mechanism was well elucidated by batch sorption experiments and DFT calculations. It was found that only TcO4- could enter into the body of ZJU-X8 through anion exchange whereas other competing anions were excluded outside. Subsequently, after interaction between TcO4- and silver ions, the electron polarizations from pyrimidine rings to Ag+ cations significantly lowered the energy level of the pi* orbital and thus reduced the pi-pi* energy gap, resulting in a red-shift in the fluorescent spectra.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available