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A simple and efficient approach to endow the controllable multi-stimuli-responsive property for the supramolecular polymer was successfully developed by rationally introducing iodine into a novel naphthalimide-functionalized pillar[5]­arene-based supramolecular polymer (PNA⊃GBP). Interestingly, by introducing iodine into the supramolecular polymer PNA⊃GBP, the iodine could not only control the optical properties and self-assembly states of PNA⊃GBP via electronic donor–acceptor effect but also control the molecular recognition properties by competitive redox reaction. Benefiting from these excellent iodine controlled multiresponse properties, the PNA⊃GBP showed selective fluorescent response for cyanide, cysteine, and mercury in supramolecular polymer gels, water solutions, and living cells with high sensitivities. The supramolecular polymer PNA⊃GBP could act as a novel smart material for selective detection CN–, Hg2+, and l-Cys.

A fast and selective method was developed for the determination of sulfonamides (SAs) in honey based on magnetic molecularly imprinted polymer. The extraction was carried out by blending and stirring the sample, extraction solvent and polymers. When the extraction was complete, the polymers, along with the captured analytes, were easily separated from the sample matrix by an adscititious magnet. The analytes eluted from the polymers were determined by liquid chromatography-tandem mass spectrometry. Under the optimal conditions, the detection limits of SAs are in the range of 1.5-4.3 ng g(-1). The relative standard deviations of intra- and interday ranging from 3.7% to 7.9% and from 4.3% to 9.9% are obtained, respectively. The proposed method was successfully applied to determine SAs including sulfadiazine, sulfamerazine, sulfamethoxydiazine, sulfamonomethoxine, sulfadimethoxine, sulfamethoxazole and sulfaquinoxaline in different honey samples. The recoveries of SAs in these samples from 67.1% to 93.6% were obtained.

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Conversion of CO 2 into valuable chemical feedstocks through artificial photosynthesis is an effective strategy to alleviate energy and environmental issues. Herein, we have developed a novel perovskite-based catalyst via in situ growing CsPbBr 3 quantum dots (QDs) on the affinal 2D CsPb 2 Br 5 nanosheets for CO 2 photoconversion. CsPbBr 3 QDs were generated by peeling off layers from their cubic counterpart; meanwhile, CsPb 2 Br 5 nanosheets were formed by heaping up the peeled layers. The resultant dual-phase composite exhibited outstanding activity and selectivity for photocatalytic conversion of gaseous CO 2 with a CO generation rate of 197.11 μmol g −1 h −1 under 300 W Xe lamp irradiation, which is 2.5 and 1.1 times higher than that of pure CsPb 2 Br 5 or CsPbBr 3 . Importantly, the fabricated dual-phase material presented extremely high stability and was able to maintain an unchangeable CO 2 conversion rate under wet air in the consecutive 10 h of recycling test. Furthermore, attributing to the in situ assembling strategy, the close contact allowed photo-generated electrons in CsPbBr 3 QDs to transfer rapidly to CsPb 2 Br 5 , and the affluent active sites in such an architecture enabled achieving enhanced CO 2 photoconversion activity. The present work provides an attractive approach for in situ constructing a consubstantial perovskite-based composite photocatalyst to ensure great stability and excellent activity for artificial photocatalytic CO 2 conversion.

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Given the global warming caused by excess CO 2 accumulation in the atmosphere, it is essential to reduce CO 2 by capturing and converting it to chemical feedstock using solar energy. Herein, a novel Cs 3 Bi 2 Br 9 /bismuth-based metal−organic framework (Bi-MOF) composite was prepared via an in situ growth strategy of Cs 3 Bi 2 Br 9 quantum dots (QDs) on the surface of Bi-MOF nanosheets through coshared bismuth atoms. The prepared Cs 3 Bi 2 Br 9 /Bi-MOF exhibits bifunctional merits for both the high capture and effective conversion of CO 2 , among which the optimized 3Cs 3 Bi 2 Br 9 /Bi-MOF sample shows a CO 2 −CO conversion yield as high as 572.24 μmol g −1 h −1 under the irradiation of a 300 W Xe lamp. In addition, the composite shows good stability after five recycles in humid air, and the CO 2 photoreduction efficiency does not decrease significantly. The mechanistic investigation uncovers that the intimate atomic-level contact between Cs 3 Bi 2 Br 9 and Bi-MOF via the coshared atoms not only improves the dispersion of Cs 3 Bi 2 Br 9 QDs over Bi-MOF nanosheets but also accelerates interfacial charge transfer by forming a strong bonding linkage, which endows it with the best performance of CO 2 photoreduction. Our new finding of bismuth-based metal−organic framework/lead-free halide perovskite by cosharing atoms opens a new avenue for a novel preparation strategy of the heterojunction with atomic-level contact and potential applications in capture and photocatalytic conversion of CO 2 .