@article {27667,
	title = {Tunable Covalent Organic Frameworks with Different Heterocyclic Nitrogen Locations for Efficient Cr(VI) Reduction, Escherichia coli Disinfection, and Paracetamol Degradation under Visible-Light Irradiation},
	journal = {Environmental Science and Technology},
	volume = {55},
	number = {8},
	year = {2021},
	pages = {5371-5381},
	publisher = {American Chemical Society},
	type = {Article},
	abstract = {Covalent organic frameworks (COFs) have great application potentials in photocatalytic water treatment. By using p-phenylenediamine with different numbers and locations of heterocyclic nitrogen atoms as a precursor, five types of COFs with different nitrogen positions were synthesized. We found that Cr(VI) photoreduction,Escherichia coli inactivation, and paracetamol degradation by COFs were heterocyclic nitrogen location-dependent. Particularly, the photocatalytic performance for all three tested pollutants by five types of COFs followed the order of the best performance for COF-PDZ with two ortho position heterocyclic N atoms, medium for COF-PMD with two meta position heterocyclic N atoms, and COF-PZ with two para position heterocyclic N atoms, and COF-PD with a single heterocyclic N atom, the worst performance for COF-1 without a heterocyclic N atom. Compared to the other COFs, COF-PDZ contained improved quantum efficiency and thus enhanced generation of electrons. The lower energy barriers and larger energy gaps of COF-PDZ contributed to its improved quantum efficiencies. The stronger affinity to Cr(VI) with lower adsorption energy of COF-PDZ also contributed to its excellent Cr(VI) reduction performance. By transferring into a more stable keto form, COF-PDZ showed great stability through five regeneration and reuse cycles. Overall, this study provided an insight into the synthesis of high-performance structure-dependent COF-based photocatalysts. {\textcopyright} 2021 American Chemical Society.},
	keywords = {\&amp;quot;2, \&amp;quot;3, 5 diaminepyrazine\&amp;quot;, 5 diaminepyrimidine\&amp;quot;, 6 diaminepyridazine\&amp;quot;, Acetaminophen, Adsorption, Aromatic compounds, article, Atoms, bacterium, binding affinity, catalysis, catalyst, Chromium, Chromium compounds, chromium hexavalent ion, controlled study, covalent organic framework, Covalent organic frameworks, crystal structure, Degradation, detection method, Disinfection, drug, Drug products, Escherichia coli, heterocyclic compound, Heterocyclic nitrogen, infrared spectroscopy, light, Location, Lower energy barriers, Metal organic framework, Metal-organic frameworks, microbial activity, nitrogen, nitrogen compound, nonhuman, nuclear magnetic resonance, Ozone water treatment, paracetamol, Performance structures, phenylenediamine, Photocatalysis, Photocatalytic performance, Photocatalytic water treatment, Photodegradation, porous polymer, pyrazine derivative, Quantum efficiency, quantum mechanics, reduction (chemistry), reduction kinetics, Regeneration and reuse, scanning electron microscopy, surface property, Synthesis (chemical), ultraviolet radiation, unclassified drug, Visible-light irradiation, Water treatment, X ray diffraction},
	isbn = {0013936X (ISSN)},
	url = {https://doi.org/10.1021/acs.est.0c07857},
	author = {F. Liu and Z. Ma and Deng, Y. and M. Wang and P. Zhou and Liu, W. and Guo, S. and Tong, M. and Ma, D.}
}
