@article{Yu2021, 
author = {Boxuan Yu and Lei Zhang and Gang Ye and Qingzhi Liu and Jiongli Li and Xudong Wang and Jing Chen and Shengming Xu and Shengqian Ma},
title = {De novo synthesis of bifunctional conjugated microporous polymers for synergistic coordination mediated uranium entrapment},
year = {2021},
journal = {Nano Research},
volume = {14},
number = {3},
pages = {788-796},
keywords = {density functional theory, adsorption, uranium, conjugated microporous polymers, synergistic coordination},
url = {https://www.sciopen.com/article/10.1007/s12274-020-3217-7},
doi = {10.1007/s12274-020-3217-7},
abstract = {This work reports a de novo synthesis of novel bifunctional conjugated microporous polymers (CMPs) exhibiting a synergistic-effect involved coordination behavior to uranium. It is highlighted that the synthetic strategy enables the engineering of the coordination environment within amidoxime functionalized CMP frameworks by specifically introducing ortho-substituted amino functionalities, enhancing the affinity to uranyl ions via forming synergistic complexes. The CMPs exhibit high Brunauer-Emmett-Teller (BET) surface area, well-developed three-dimensional (3D) networks with hierarchical porosity, and favorable chemical and thermal stability because of the covalently cross-linked structure. Compared with the amino-free counterparts, the adsorption capacity of bifunctional CMPs was increased by almost 70%, from 105 to 174 mg/g, indicating evidently enhanced binding ability to uranium. Moreover, new insights into coordination mechanism were obtained by in-depth X-ray photoelectron spectroscopy (XPS) analysis and density functional theory (DFT) calculation, suggesting a dominant role of the oxime ligands forming a 1:1 metal ions/ligands (M/L) coordination model with uranyl ions while demonstrating the synergistic engagement of the amino functionalities via direct binding to uranium center and hydrogen-bonding involved secondary-sphere interaction. This work sheds light on the underlying principles of ortho-substituted functionalities directed synergistic effect to promote the coordination of amidoxime with uranyl ions. And the synthetic strategy established here would enable the task-specific development of more novel CMP-based functional materials for broadened applications.}
}