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Photo-Annealing of Merocyanine Aggregates
摘要： In this work we elucidate the fundamental difference between aggregate formation of donor-π-acceptor merocyanines in their electronic ground and excited states. While increasing the π-bridge size favors formation of π-stacked aggregates in the dark, irradiation with visible light causes reorientation of the dyes to form prototype H-aggregates with compensating dipole moments. This photo-annealing changes the supramolecular structure and its UV-vis spectroscopic properties dramatically, thus being of importance for the function of active layers composed of these dyes. Aggregates of the ground state dyes are bound cooperatively through ππ-London dispersion interactions and hydrogen bonds between the polar α-cyano-carboxylic acid groups. However, charge transfer upon photoexcitation leads to repulsion of the polar acid groups. Electronic excitation of the dyes approximately doubles the ground state dipole moment, thus driving molecular reorientation into prototype H-aggregate structures. We show that this photo-induced supramolecular rearrangement can disrupt the large polymeric aggregates formed in the dark. The photo-induced supramolecular structural changes reported in this work will influence the performance of optoelectronic devices composed of these structures and must be controlled to avoid morphological decomposition of active layers upon operation.
关键词： merocyanines,photo-annealing,H-aggregates,supramolecular structure,UV-vis spectroscopy,dipole moments,aggregate formation
更新于2025-09-23 15:21:21
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Increasing Membrane Permeability by Increasing the Polymer Crystallinity: The Unique Case of Polythiophenes
摘要： It is generally accepted in membrane technology that crystalline zones in polymeric membranes do not contribute to transport of liquids or gases. In the current study, poly(3-alkylthiophene)s (P3ATs), i.e., homopolymers and random copolymers, were synthesized to study the influence of the supramolecular organization on membrane gas separations. The monomers were polymerized via KCTCP, and GPC analysis shows that the polymers have a narrow dispersity. DSC analysis of the polymers reveals that the homopolymers, in contrast to the copolymers, crystallized, confirming their higher degree of supramolecular organization. This was supported by UV?vis absorption spectra of the polymer films, where a red-shift and a characteristic shoulder absorption peak around 600 nm were observed for the homopolymers, while absent for the copolymers. More surprisingly, the homopolymers were found to be 2 orders of magnitude more permeable to CO2 than the copolymers and also more selective.
关键词： selectivity,gas separations,permeability,membrane technology,supramolecular organization,poly(3-alkylthiophene)s,crystallinity
更新于2025-09-23 15:21:21
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Supramolecular Photothermal Nanomaterials as an Emerging Paradigm toward Precision Cancer Therapy
摘要： The concept of the “supramolecular photothermal effects” refers to the collection property and photothermal conversion efficiency resulting from the supramolecular assembly of molecular photothermal sensitizers. This review considers organic supramolecular photothermal materials assembled at the nanoscale via various molecular self-assembly strategies and associated with the organization of multiple noncovalent interactions. In these materials, the individual photosensitizer molecules are typically aggregated through self-assembly in a certain form that exhibits enhanced biostability, increased photothermal conversion efficiency with photoluminescence quenching, and improved photothermal therapeutic effects in comparison with those of the monomeric photosensitizer molecules. These supramolecular photothermal effects are controlled or influenced by intermolecular noncovalent interactions, especially the hydrophobic effects, which are distinct from the mechanisms of conventional sensitizer molecules and polymers and inorganic photothermal agents. A focus lies on how self-assembly strategies give rise to supramolecular photothermal effects, including polymer and protein fabrication, small molecule self-assembly, and the construction of donor–acceptor binary systems. Emphases are placed on the rational design of supramolecular photothermal nanomaterials, drug delivery, and in vivo photothermal therapeutic effects. Finally, the key challenges and promising prospects of these supramolecular photothermal nanomaterials in terms of both technical advances and clinical translation are discussed.
关键词： photothermal therapy,nanomaterials,cancer therapy,supramolecular photothermal effects,self-assembly
更新于2025-09-23 15:21:21
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Transparent, flexible MAPbI3 perovskite microwire array passivated with ultra-hydrophobic supramolecular assembly for stable and high-performance photodetectors
摘要： The emergence of organic-inorganic hybrid perovskites (OHPs) has revolutionised the potential performance of optoelectronic devices, most perovskites are opaque and hence incompatible with transparent optoelectronics, and sensitive to environmental degradation. Here, a single-step fabrication of ultra-long MAPbI3 perovskite microwire array over a large-area using stencil lithography based on a sequential vacuum sublimation. The environmental stability of MAPbI3 is empowered a newly designed and synthesized transparent supramolecular self-assembly, based on a mixture of two tripodal L-Phe-C11H23/C7F15 molecules, which showed a contact angle of 105° and served as ultra-hydrophobic passivation layer for more than 45 days in ambient atmosphere. The MAPbI3 microwire array passivated with supramolecular self-assembly demonstrate for the first time both excellent transparency of ~89% at 550 nm and remarkable photoresponse with photo-switching ratio of ~104, responsivity of 789 A/W, detectivity of 1014 Jones, linear dynamic range of ~ 122 dB, and rise time of 432 μs. Furthermore, the photodetector fabricated on flexible PET substrate demonstrated robust mechanical flexibility even beyond 1200 bending cycles. Therefore, the scalable stencil lithography and supramolecular passivation approaches have the potential to deliver next-generation transparent, flexible, and stable optoelectronics.
关键词： transparency,stencil lithography,photodetectors,MAPbI3,supramolecular self-assembly,flexibility,organic-inorganic hybrid perovskites,environmental stability
更新于2025-09-23 15:21:01
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Macrocycle encapsulation triggered supramolecular pKa shift: A fluorescence indicator for detecting octreotide in aqueous solution
摘要： Supramolecular pKa shifts, have attracted much attention in catalytic and biomimetic studies because of their excellent property to modify the acidity or basicity of the substrate in aqueous media by host-guest inclusion. Here, Fluorescence indicator displacement based on cucurbit[8]uril encapsulation of the dye acridine leads to the recognition of the peptide drug octreotide in aqueous solution via distinctive pH signals was expolited. This is thought to be a result of competitive host-guest interactions involving a supramolecular pKa shift.
关键词： Supramolecular pKa shift,Drug octreotide,Cucurbit[8]uril,Fluorescence indicator displacement,Acridine
更新于2025-09-23 15:21:01
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Imaging Supramolecular Morphogenesis with Confocal Laser Scanning Microscopy at Elevated Temperatures
摘要： The morphogenesis of supramolecular assemblies is a highly dynamic process that has only recently been recognized, and our understanding of this phenomenon will require imaging techniques capable of crossing scales. Shape transformations depend both on the complex energy landscapes of supramolecular systems and the kinetically controlled pathways that define their structures and functions. We report here the use of confocal laser scanning microscopy coupled with a custom-designed variable-temperature sample stage that enables in situ observation of such shape changes. The submicrometer resolution of this technique allows for real-time observation of the nanostructures in the native liquid environments in which they transform with thermal energy. We use this technique to study the temperature-dependent morphogenic behavior of peptide amphiphile nanofibers and photocatalytic chromophore amphiphile nanoribbons. The variable-temperature confocal microscopy technique demonstrated in this work can sample a large volume and provides real-time information on thermally induced morphological changes in the solution.
关键词： in situ microscopy,confocal microscopy,nanofibers,nanoribbons,supramolecular assembly
更新于2025-09-23 15:21:01
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Dopant-free hole transporting materials with supramolecular interactions and reverse diffusion for efficient and modular p-i-n perovskite solar cells
摘要： The rational design of dopant-free organic hole-transporting layer (HTL) materials is still a challenge for realizing high-efficient and stable p-i-n planar perovskite solar cells (pero-SCs). Here, we synthesized two π-conjugated small-molecule HTL materials through tailoring the backbone and conjugated side chain to carefully control molecular conformation. The resultant BDT-TPA-sTh containing a planar fused benzo[1,2-b:4,5-b′]dithiophene (BDT) core and a conjugated thiophene side chain showed the planar conformation. X-ray crystallography showed a favorable stacking model in solid states under the parallel-displaced π-π and additional S-π weak-bond supramolecular interactions, thus achieving an obviously increased hole mobility without dopants. As an HTL material in p-i-n planar pero-SCs, the marginal solubility of BDT-TPA-sTh enabled inverse diffusion into the perovskite precursor solution for assisting the subsequent perovskite film growth and passivating the uncoordinated Pb2+ ion defects. As a result, the planar p-i-n pero-SCs exhibited a champion power conversion efficiency (PCE) of 20.5% and enhanced moisture stability. Importantly, the BDT-TPA-sTh HTL material also showed weak thickness-photovoltaic dependence, and the pero-SCs with blade-coated BDT-TPA-sTh as a HTL achieved a 15.30% PCE for the 1-cm2 modularized device. This HTL material design strategy is expected to pave the way toward high-performance, dopant-free and printing large-area planar p-i-n pero-SCs.
关键词： hole-transporting materials,p-i-n planar perovskite solar cells,reverse diffusion,supramolecular interactions
更新于2025-09-23 15:21:01
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Photoactive Functional Soft Materials (Preparation, Properties, and Applications) || Photoresponsive Supramolecular Polymers
摘要： According to the definition by Meijer and coworkers in their seminal review [1], supramolecular polymers are polymeric assemblies of small molecular units that are brought together through reversible and directional noncovalent interactions, leading to polymeric properties in solution and bulk states [1–5]. Owing to the reversible nature of their main‐chain formation, supramolecular polymers have attracted considerable attention as highly stimuli‐responsive polymeric materials compared to conventional polymer counterparts. Needless to say, supramolecular polymers have high responsiveness in terms of “degree of polymerization” to temperature change mainly due to entropic reasons, and to solvent media mainly due to enthalpic reasons. Such high responsiveness to external environment has enabled not only the exploration of temperature‐ and solvent‐dependent supramolecular polymer systems, but also the analyses of the supramolecular polymerization process regulated by these parameters [6]. From a technical viewpoint, furthermore, supramolecular polymers have another advantage over conventional polymers, i.e. quite ambient polymerization conditions without using any chemical reagents. This allows more flexible monomer design and enables introduction of a wide variety of functional molecules into supramolecular monomers.
关键词： stimuli-responsive,photoresponsive,supramolecular polymers,polymerization,noncovalent interactions
更新于2025-09-23 15:21:01
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Building from Ga-porphyrins: Synthesis of Ga-Acetylide complexes using acetylenes and polyynes
摘要： Multidimensional, conjugated building blocks have been formed through the axial coordination of polyynes to the central Ga atom of tetraarylporphyrins. Electron deficient pentafluorophenyl substituents in the meso-positions provide more stable s-acetylide complexes to Ga than analogous structures with tert-butylphenyl groups. Mono-, di-, and triynes have been used, including a pyridyl endcapped diyne that allows for formation of porphyrin triads through coordination of the pyridyl ligand to a Ru porphyrin.
关键词： hierarchical assembly,Ga-porphyrin,polyyne,supramolecular assembly,axial s-acetylide
更新于2025-09-23 15:21:01
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Controlled Synthesis of PdII and PtII Supramolecular Copolymer with Sequential Multiblock and Amplified Phosphorescence
摘要： Supramolecular copolymers constitute a fundamental new class of functional materials attracting burgeoning interest, but examples that display phosphorescence and long-lived excited states are rare. Herein, we describe the synthesis of sequential phosphorescent multi-block supramolecular copolymers in one and multiple dimensions using pincer PtII and PdII complexes as building blocks by manipulating out-of-equilibrium self-assemblies via the living supramolecular polymerization approach. Doping a small amount of PtII complexes (2 mol %) into the PdII assemblies significantly boosted the emission efficiency and radiative decay rate constant (Fem = 3.7%, kr = 1.8 3 104 s?1 in PdII assemblies; Fem = 76.2%, kr = 58.6 3 104 s?1 in PtII-PdII co-assemblies), which is ascribed to an external heavy-atom spin-orbital coupling effect arising from the doped PtII complex with a delocalized 3[ds*/p*] excited state. The findings on PtII and PdII supramolecular copolymers with controlled sequences and greatly enhanced phosphorescence efficiencies open the door to new photofunctional and responsive luminescent metal-organic supramolecular materials.
关键词： Living supramolecular polymerization,PtII and PdII complexes,Phosphorescence,External heavy-atom effect,Supramolecular copolymers
更新于2025-09-23 15:19:57