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Afterglow or long persistent luminescence (LPL) materials have received great attention due to their potential applications. In this report, we synthesized two metal–organic coordination polymers, LIFM-ZJY-1 and LIFM-ZJY-2 by the self-assembly of 9-(4-carboxybenzyl)-9H-carbazole-3,6-dicarboxylic acid with Cd(II) and Zn(II) metal salts, which showed excitation wavelength, temperature and time-dependence afterglow properties, based on multiple excited states that can be regulated by external stimuli. Besides, theoretical calculation studies proved the experimental results of dual-fluorescence emission with Kasha and anti-Kasha characters. Given the unique fluorescence and dynamic afterglow properties, LIFM-ZJY-1 and LIFM-ZJY-2 are demonstrated for applications in multidimensional dynamic information encryption. These findings will open an avenue to explore anti-Kasha and dynamic afterglow materials and significantly broaden their applications. [ABSTRACT FROM AUTHOR]

As a unique type of supramolecular self‐assemblies, crystalline host‐guest aggregates have attracted extensive interests in multiple application fields. Herein, a crystalline host‐guest aggregate LIFM‐HG1 was obtained with curcubit[8]uril as the host and carboxypyridinium salt as the guest. Single‐crystal structural analysis indicates that the presence of abundant weak interactions in LIFM‐HG1 provides a rigid environment for the guest molecule and effectively blocks the external quenchers. Spectral analysis and theoretical calculations confirm the presence of robust triplet energy levels in LIFM‐HG1. Even more impressively, the intersystem crossing channels of the guest molecules are greatly opened up after the formation of the crystalline host‐guest aggregate, resulting in a large kisc of 6.70 × 107 s−1 at room temperature for LIFM‐HG1 (which is ∼0 for pure guest), leading to fascinating multichannel (including one‐photon, two‐photon, and X‐ray) excited LPL properties. In addition, the crystalline LIFM‐HG1 has a much higher triplet state luminescence efficiency under X‐ray and two‐photon excitation than that under single‐photon excitation (AP/AF = 86.8, 44.8, 10.7 under the three circumstances, respectively). And the phosphorescent emission intensity of LIFM‐HG1 is 27.6 times higher than that of the crystalline guest under X‐ray excitation. As a result, LIFM‐HG1 shows a long afterglow retention time under both single‐ and two‐photon excitation, and an impressive afterglow retention time of 1 s under X‐ray excitation. Furthermore, the excellent lysosomal targeting and low cytotoxicity by the formation of host‐guest aggregate makes LIFM‐HG1 promising to be used as a novel lysosomal‐targeted two‐photon excited phosphorescent tracer. [ABSTRACT FROM AUTHOR]

The rhizosphere is an important place for material exchange between medicinal plants and soil. Root exudates are the medium of material and signal exchange between plants and soil and are the key factors in the regulation of rhizosphere microecology. Rhizosphere microorganisms are an important part of the rhizosphere microecology of medicinal plants, and the interaction between root exudates and rhizosphere microorganisms has an important influence on the growth and quality formation of medicinal plants. Rational utilization of the interaction between root exudates and rhizosphere microorganisms of medicinal plants is one of the important ways to ensure the healthy growth of medicinal plants and promote the development of ecological planting of Chinese medicinal materials. In the paper, the research status of root exudates and rhizosphere microorganisms of medicinal plants in recent years was summarized. The interaction mechanism between root exudates and rhizosphere microorganisms of medicinal plants, as well as the influence of rhizosphere microorganisms on the growth of medicinal plants, were analyzed. In addition, the advantages and promoting effects of intercropping ecological planting mode on rhizosphere microecology of medicinal plants and quality improvement of Chinese medicinal materials were explained, providing a good basis for the study of the interaction among medicinal plants, microorganisms, and soil. Furthermore, it could produce important theoretical and practical significance for the ecological planting and sustainable utilization of medicinal plants.

By synergistically employing four key strategies: (I) introducing tetraphenylethylene groups as the central core unit with aggregation-induced emission (AIE) properties, (II) optimizing the π-conjugated length by extending the building block branches, (III) incorporating flexible groups containing ethylenic bonds, and (IV) applying crystal engineering to attain dense stacking mode and highly twisty conformation, we successfully synthesized a series of hydrogen-bonded organic frameworks (HOFs) exhibiting exceptional one/two-photon excited fluorescence. Notably, when utilizing the fluorescently superior building block L2, HOF-LIFM-7 and HOF-LIFM-8 exhibiting high quantum yields (QY) of 82.1 % and 77.1 %, and ultrahigh two-photon absorption (TPA) cross-sections of 148959.5 GM and 123901.1 GM were achieved. These materials were successfully employed in one and two-photon excited lysosome-targeting cellular imaging. It is believed that this strategy, combining building block optimization and crystal engineering, holds significant potential for guiding the development of outstanding fluorescent HOF materials., (© 2023 Wiley-VCH GmbH.)

The multiple metastable excited states provided by excited-state intramolecular proton transfer (ESIPT) molecules are beneficial to bring temperature-dependent and color-tunable long persistent luminescence (LPL). Meanwhile, ESIPT molecules are intrinsically suitable to be modulated as D-π-A structure to obtain both one/two-photon excitation and LPL emission simultaneously. Herein, we report the rational design of a dynamic Cd II coordination polymer (LIFM-106) from ESIPT ligand to achieve the above goals. By comparing LIFM-106 with the counterparts, we established a temperature-regulated competitive relationship between singlet excimer and triplet LPL emission. The optimization of ligand aggregation mode effectively boost the competitiveness of the latter. In result, LIFM-106 shows outstanding one/two-photon excited LPL performance with wide temperature range (100-380 K) and tunable color (green to red). The multichannel radiation process was further elucidated by transient absorption and theoretical calculations, benefiting for the application in anti-counterfeiting systems., (© 2023 Wiley-VCH GmbH.)

Organic LPL (long-persistent luminescence) materials have sparked extensive research interest due to the ultralong-lived triplet states. Although numerous organic LPL materials have been reported, most of the triplet emission was static and monotonous. Therefore, LPL materials with dynamic triplet emission are urgently required. A triamino-s-triazine derivative 1 with dynamic LPL was fabricated. The single-crystal structure shows that the abundant intermolecular interactions and small free volume restrict the molecular motion and avoid the quenchers. Spectral and theoretical calculations upheld the existence of multiple excited states in 1, and the migration of electrons between multiple excited states is very sensitive to external stimuli. By modulating the stimulus, the residence of electrons in different triplet states can be manipulated to achieve RGB LPL. Importantly, blue LPL was achieved by manipulating the anti-Kasha emission. And the red LPL can still be observed at high temperature., (© 2022 Wiley-VCH GmbH.)