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Abstract The effect of rare earth (RE) single atoms on photocatalytic activity is very complex due to its special electronic configuration, which leads to few reports on the RE single atoms. Here, Dy3+single atom composite photocatalysts are successfully constructed based on both the special role of Dy3+and the special advantages of CdS/g‐C3N4heterojunction in the field of photocatalysis. The results show that an efficient way of electron transfer is provided to promote charge separation, and the dual functions of CO2molecular activation of rare‐earth single atom and 4flevels as electron transport bridge are fully exploited. It is exciting that under visible‐light irradiation, the catalytic performance of CdS:Dy3+/g‐C3N4is≈6.9 times higher than that of pure g‐C3N4. The catalytic performance of CdS:Dy3+and CdS:Dy3+/g‐C3N4are≈7 and≈13.7 times higher than those of pure CdS, respectively. Besides, not all RE ions are suitable for charge transfer bridges, which is not only related to the 4flevels of RE ions but also related to the bandgap structure of CdS and g‐C3N4. The pattern of combining single‐atom catalysis and heterojunction opens up new methods for enhancing photocatalytic activity.
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Installation of synergistic binding sites onto porous organic polymers for efficient removal of perfluorooctanoic acid
Abstract Herein, we report a strategy to construct highly efficient perfluorooctanoic acid (PFOA) adsorbents by installing synergistic electrostatic/hydrophobic sites onto porous organic polymers (POPs). The constructed model material of PAF-1-NDMB (NDMB = N,N-dimethyl-butylamine) demonstrates an exceptionally high PFOA uptake capacity over 2000 mg g−1, which is 14.8 times enhancement compared with its parent material of PAF-1. And it is 32.0 and 24.1 times higher than benchmark materials of DFB-CDP (β-cyclodextrin (β-CD)-based polymer network) and activated carbon under the same conditions. Furthermore, PAF-1-NDMB exhibits the highestk2value of 24,000 g mg−1h−1among all reported PFOA sorbents. And it can remove 99.99% PFOA from 1000 ppb to <70 ppt within 2 min, which is lower than the advisory level of Environmental Protection Agency of United States. This work thus not only provides a generic approach for constructing PFOA adsorbents, but also develops POPs as a platform for PFOA capture.
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- PAR ID:
- 10381669
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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