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The Cu4I4-MOF-based mixed matrix membranes (MMMs) can be readily prepared by one-step in situ self-assembly of a tri-armed oxadiazole-bridged ligand and CuI in polymer binder solution under ambient conditions. The visual and luminescent HCl(g) sensing detecting limits of the resulting Cu4I4-MOF-based MMMs are 3.2 and 1.6 ppb, respectively, and the response time is less than 1 min.

The moisture-swing sorbent of amine-based anion exchange resins is one of the most promising materials for direct carbon capture from ambient air to alleviate excessive emissions of CO 2 . In this study, how the physical and chemical properties of amine-based anion exchange resins affect their carbon capture performances is studied systematically, through different kinds of resins. Contrary to previous understandings, the effect of the chemical functional groups on the overall capture performance is found to far outweigh that of the physical properties. It is found that the main property that determines the absorption capacity is the chemical one, i.e., the amine functional groups, while properties dominating the absorption kinetics are the physical ones, i.e., particle size and microporous structures. The absorption capacity of resins loaded with strong amine groups is strikingly higher than that with weak amine groups. The mechanism is explored by a combination of molecular dynamics and quantum chemical calculations. The most superior sorbent is the macro-porous strong base resin due to its strong amine groups and large inner pore sizes. The present study provides new insights into selecting suitable absorbents or preparing better ones for enhanced direct air capture of CO 2 .

Metastable Bi 3+ self-doped NaBiO3 (NBO) nanosheets were prepared by using acidic hydrolysis of NaBiO3·2H2O in HNO3 solutions. It was found that the as-prepared NBO nanosheets showed both chemical oxidation ability and photocatalytic oxidation activity for the degradation of carbamazepine under visible light irradiation. The pseudo-zero order reaction kinetic constant for the photodegradation of carbamazepine (20 μmol L −1 ) over the metastable NBO nanosheets was 0.087 min −1 , being 10.4 and 5.0 times that of the photocatalytic oxidation over the stable NBO nanosheets and the chemical oxidation over the metastable NBO nanosheets © 2016. This manuscript version is made available under the Elsevier user license http://www.elsevier.com/open-access/userlicense/1.0/in dark, respectively. The enhanced photodegradation of carbamazepine over the metastable NBO nanosheets was mainly attributed to a reaction process of photocorrosion of the NBO nanosheets, which increased generation of singlet oxygen from the lattice oxygen of NBO and promoted a synergistic effect between the chemical oxidation and the photocatalytic oxidation. Singlet oxygen and photo-generated holes were identified as the major reactive species for photodegradation of carbamazepine. By a rough estimation, the (dark) chemical oxidation, photocorrosion process and photocatalysis contributed 19.4%, 60% and 20.6% of the total degradation of carbamazepine, respectively. Based on the identification of intermediates by GCand LC-MS, two degradation pathways of carbamazepine in both chemical oxidation system and photocatalytic system were proposed. The developed dual-reactive-species-based photocatalysis may be a useful technology for the purification of water containing carbamazepine.