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Thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP) are two highly applicable emissive processes due to their time-resolved characteristics and their ability to respond to external stimuli. They have recently been integrated for comprehensive use in some solid-state luminogens; however, there remains a lack of molecular systems that can integrate them in the solution aggregated state, which considerably limits relevant biological applications. In this study, we present a molecular design enabling aggregation-induced TADF-RTP dual emission in the solution aggregated state, relying on the coexistence of T-1-to-S-1 and T-1-to-S-0 electronic processes in push-pull structures. This dual emission feature constitutes a broad spectral band with full width at half-maximum up to 175 nm, providing the ability to select different channels for biological detection and imaging. Moreover, deoxygenation is shown to promote molecular aggregation, leading to a significantly strengthened dual emission that enables a high-contrast hypoxia probing effect. These results not only reveal new photophysical mechanisms on organic molecules but also expand the detection functionality of luminescent materials in the biological field., Funding Agencies|National Natural Science Foundation of China [22275038]; NSFC/China [K2024-33]; State Key Laboratory of Molecular Engineering of Polymers (Fudan University) [2130011540027, NAISS 2023/5-77]; Ningbo University of Technology [2020-04600]; Swedish Research Council [2009-00971]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University [212-0136]; Olle Engkvists Stiftelse (Sweden)

Confining luminophores into modified hydrophilic matrices or polymers is a straightforward and widely used approach for afterglow bioimaging. However, the afterglow quantum yield and lifetime of the related material remain unsatisfactory, severely limiting the using effect especially for deep-tissue time-resolved imaging. This fact largely stems from the dilemma between material biocompatibility and the quenching effect of water environment. Herein an in situ metathesis promoted doping strategy is presented, namely, mixing approximate to 10-3 weight ratio of organic-emitter multicarboxylates with inorganic salt reactants, followed by metathesis reactions to prepare a series of hydrophilic but water-insoluble organic-inorganic doping afterglow materials. This strategy leads to the formation of edible long-afterglow photoluminescent materials with superior biocompatibility and excellent bioimaging effect. The phosphorescence quantum yield of the materials can reach dozens of percent (the highest case: 66.24%), together with the photoluminescent lifetime lasting for coupes of seconds. Specifically, a long-afterglow barium meal formed by coronene salt emitter and BaSO4 matrix is applied into animal experiments by gavage, and bright stomach afterglow imaging is observed by instruments or mobile phone after ceasing the photoexcitation with deep tissue penetration. This strategy allows a flexible dosage of the materials during bioimaging, facilitating the development of real-time probing and theranostic technology. A universal strategy is proposed to construct edible photoluminescent long-afterglow materials by embedding luminophore multicarboxylates into a series of inorganic salt lattices. Particularly, edible afterglow barium meal formed by coronene salt doped BaSO4 can be applied into gastrointestinal afterglow imaging captured by instruments or mobile phone. image, Funding Agencies|National Natural Science Foundation of China; [21975046]; [22275038]

Thiahexaphyrinone 1 and thia-dipyrrin-appended corrorin 2 have been synthesized. Surprisingly, further oxidation of compound 2 with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in dichloromethane afforded dimer 3 with two molecules of compound 2 linked at the alpha-carbon atoms of the thienyl units. Treatment of compound 3 with DDQ in MeOH and SnCl2 in tetrahydrofuran/H2O afforded the dimethoxy-attached dimer 4 and hydrogenated dihydroxy-attached dimer 5, respectively. These results provide the first examples for synthesizing thiophene-linked porphyrinoid dimers with tunable near-infrared absorption and chirality., Funding Agencies|National Natural Science Foundation of China; East China University of Science and Technology (ECUST) [22131005, 22201074, 22075077, 21971063]; National Natural Science Foundation of China [23QA1402100]; Shanghai Rising-Star Program [23ZR1415600, 22ZR1416100]; Natural Science Foundation of Shanghai [2018-05973, 2020-04600]; Swedish Research Council [JPMXS0320220200]; Ministry of Education, Culture, Sports, Science and Technology (MEXT) Leading Initiative for Excellent Young Researchers

To further enrich the coordination chemistry of hexaphyrins and probe the underlying property-structural correlations, N-confused dithiahexaphyrin(1.1.1.1.1.0) (1) with 26 pi-electron H & uuml;ckel aromaticity was synthesized. Based on its unprecedented two unsymmetrical cavities, five palladium complexes 2, 3, 4-Ph, 4-Cl and 5 have been successfully synthesized under various coordinations. Thus, two mono-Pd(II) complexes 2 and 3 with the Pd(II) atom coordinated in the two different cavities were obtained by treating 1 with palladium reagents PdCl2, and (PPh3)(2)PdCl2 respectively. On this basis, bis-Pd(II) complexes 4-Ph and 4-Cl were synthesized by treating 2 and 3 with (PPh3)(2)PdCl2 and PdCl2, respectively. As a result, both 4-Ph and 4-Cl contain two Pd(II) atoms coordinated within the two cavities, with one of the Pd(II) atoms further coordinated to a triphenylphosphine ligand in addition to an anionic ancillary ligand of Ph- and Cl-, respectively. Notably, a further contracted mono-Pd(II) complex 5 was synthesized by treating 1 with Pd(PPh3)(4) by eliminating one of the meso-carbon atoms together with the corresponding C6F5 moiety. These complexes present tunable 26 pi aromaticity and NIR absorption up to 1060 nm. This work provides an effective approach for developing distinctive porphyrinoid Pd(II) complexes from a single porphyrinoid, without resorting to tedious syntheses of a series of porphyrinoid ligands., Funding Agencies|Shanghai Rising-Star Program [22131005, 21971063, 22201074, 22075077]; NSFC; Fundamental Research Funds for the Central Universities [23QA1402100]; Shanghai Rising-Star Program [23ZR1415600, 22ZR1416100]; Natural Science Foundation of Shanghai [2018-05973, 2020-04600]; Swedish Research Council

Molecular emitters with multi-emissive properties are in high demand in numerous fields, while these properties basically depend on specific molecular conformation and packing. For amorphous systems, special molecular arrangement is unnecessary, but it remains challenging to achieve such luminescent behaviors. Herein, we present a general strategy that takes advantage of molecular rigidity and S1-T1 energy gap balance for emitter design, which enables fluorescence-phosphorescence dual-emission properties in various solid forms, whether crystalline or amorphous. Subsequently, the amorphism of the emitters based polymethyl methacrylate films endowed an in situ regulation of the dual-emissive characteristics. With the ratiometric regulation of phosphorescence by external stimuli and stable fluorescence as internal reference, highly controllable luminescent color tuning (yellow to blue including white emission) was achieved. There properties together with a persistent luminous behavior is of benefit for an irreplaceable set of optical information combination, featuring an ultrahigh-security anti-counterfeiting ability. Our research introduces a concept of eliminating the crystal-form and molecular-conformational dependence of complex luminescent properties through emitter molecular design. This has profound implications for the development of functional materials. A molecular structural strategy enabling single emitter based dual-emission properties in various solid forms is presented. The developed amorphous films endow in situ regulation of the dual-emissive characteristics to show highly controllable multiple luminescent color tuning (yellow to blue including white emission), which benefits to the construction of an irreplaceable set of optical information combination.image, Funding Agencies|National Natural Science Foundation of China [2022-06725]; Swedish Research Council [22275038]; Russian Scientific Foundation [NAISS 2023/5-77]; National Academic Infrastructure for Supercomputing in Swede at the National Supercomputer Centre (NSC) at Linkoeping University; [2020-04600]; [23-73-10081]