Controlling supramolecular copolymerization of alkynylplatinum(ii) terpyridine complexes: from isodesmic to cooperative mechanisms.

Recently, cooperative supramolecular polymerization has garnered considerable attention due to its significant potential for enabling controlled chain-growth polymerization, which offers a route to achieving a well-defined degree of polymerization and low polydispersity. In this study, we synthesized two distinct alkynylplatinum(ii) complexes, one bearing a saturated long alkyl chain (Pt-Sat-C18) and another containing a diacetylene moiety within a long alkyl chain (Pt-DA-C25). Spectroscopic analyses revealed that Pt-Sat-C18 undergoes supramolecular polymerization via an isodesmic pathway, while Pt-DA-C25 assembles cooperatively. Intriguingly, the mechanism of supramolecular copolymerization could be tuned by varying the composition ratios: transitioning from an isodesmic to a cooperative pathway was achieved by increasing the proportion of Pt-DA-C25. Moreover, UV irradiation prompted a shift from an isodesmic to a cooperative assembly mechanism. Morphologically, self-assembled Pt-Sat-C18 resulted in left-handed fibrillar structures, whereas Pt-DA-C25 led to left-handed tubular assemblies. Supramolecular co-assembly further revealed helical ribbon or tubular structures. Photoluminescent properties were also observed, with emission spectra centered at approximately 650 nm, attributed to the formation of excimer species facilitated by strong Pt⋯Pt interactions. To elucidate the mechanisms underlying these supramolecular polymerizations, temperature-dependent UV-visible spectroscopy was conducted during the cooling/heating processes, and thermodynamic parameters for both isodesmic and cooperative pathways were quantitatively assessed through curve fitting.

Chiral Supramolecular Multiblock Copolymerization Accompanying Chirality Transfer in Heterostructures via Living Chain Growth.

We report the unique synthesis of chiral supramolecular tri- and penta-BCPs with controllable chirality using kinetically adjusted seeded supramolecular copolymerization in THF and DMSO (99 : 1, v/v). Tetraphenylethylene (d- and l-TPE) derivatives bearing d- and l-alanine side chains formed thermodynamically favored chiral products via a kinetically trapped in monomeric state with a long lag phase. In contrast, achiral TPE-G containing glycine moieties did not form a supramolecular polymer owing to the energy barrier in its kinetically trapped state. We show that the copolymerization of the metastable states of TPE-G not only enables the generation of supramolecular BCPs by the seeded living growth method, but also transfers chirality at the seed ends. This research demonstrates the generation of chiral supramolecular tri- and penta-BCPs with B-A-B, A-B-A-B-A, and C-B-A-B-C block patterns accompanying chirality transfer via seeded living polymerization.

Solvent-Dependent Self-Assembly of a Pillar[5]arene-Based Poly-Pseudo-Rotaxane Linked and Threaded by Silver(I) Trifluoroacetate: A Double Role.

In the supramolecule area, the fabrication of a new concept called polyrotaxanes or poly-pseudo-rotaxanes remains challenging. We herein report the formation of a poly-pseudo-rotaxane in which the same salt-type guest serves both linking and threading in the resulting structure. The combination of A1/A2-thiopyridyl pillar[5]arene (L) and silver(I) trifluoroacetate in CHCl3/CH3OH afforded a one-dimensional (1D) poly-pseudo-rotaxane. In this structure, to our surprise, the AgCF3CO2 guest not only links the di-armed L ligands via an infinite -L-Ag-L-Ag- arrangement but also threads into a pillar[5]arene cavity in a dimer form, (AgCF3CO2)2. In contrast, the same reaction in CH2Cl2/CH3OH yielded a simple 1D coordination polymer because an included CH2Cl2 molecule in the pillar[5]arene cavity prevents the threading of the silver(I) trifluoroacetate guest. Comparative 1H- and 19F-NMR studies support the solvent-dependent poly-pseudo-rotaxane formation at a lower concentration of L.

Unexpected Solvent-Dependent Self-Assembly of Alkali Metal Complexes of Calix[6]-mono-crown-4: Dinuclear Bowls, a Pseudo-Capsule, and a One-Dimensional Polymer.

1,4-Bridged calix[6]-mono-crown-4 (H4L) capable of metal binding was employed, and the influence of solvent variations on the formation of alkali metal complexes (1-6) was investigated. In the crystal, the bowl-shaped H4L host contains one water molecule in a good-fit fashion via H-bonds. When the H4L host was reacted with alkali metal hydroxides (M = Na, K, Rb, and Cs) in chloroform/methanol (solvent A), anion-free dinuclear bowl-shaped complexes of type [M2(H2L)] were isolated regardless of the metal ions. In the dinuclear bowl complexes 1-4, two metal ions (M1 and M2) show different binding behaviors: one (M1) locates inside the pocket like an "egg-in-nest", and the other (M2) positions above the M1 interacting with the calix rim. When chloroform/acetonitrile (solvent B) was used in potassium(I) complexation, interestingly, an elegant pseudo-capsule-type quadrunuclear complex 5 was isolated. In 5, two dipotassium(I) bowls in a rim-to-rim arrangement are triply bridged by one water and two acetonitrile molecules like a magic glue. However, in dichloromethane/methanol (solvent C), cesium(I) yielded an infinite product 6 in which dicesium(I) bowls are linked by cation-π interactions, giving rise to a one-dimensional zigzag coordination polymer. Taken collectively, all products share a dinuclear bowl unit, some of which are further extended to the pseudo-capsule or polymeric array, depending on the solvents. The results suggest the solvent variation as a versatile engineering tool and present a perspective on the metallosupramolecules of calix[6]-mono-crowns with monomer, dimer (e.g., pseudo-capsule), and polymer topologies.

Circularly Polarized Luminescence Active Supramolecular Nanotubes Based on PtII Complexes That Undergo Dynamic Morphological Transformation and Helicity Inversion.

Circularly polarized luminescence (CPL) with tunable chirality is currently a challenging issue in the development of supramolecular nanomaterials. We herein report the formation of helical nanoribbons which grow into helical tubes through dynamic helicity inversion. For this, chiral PtII complexes of terpyridine derivatives, namely S-trans-1 and R-trans-1, with respective S- and R-alanine subunits and incorporating trans-double bonds in the alkyl chain were prepared. In DMSO/H2 O (5 : 1 v/v), S-trans-1 initially forms a fibrous self-assembled product, which then undergoes dynamic transformation into helical tubes (left-handed or M-type) through helical ribbons (right-handed or P-type). Interestingly, both helical supramolecular architectures are capable of emitting CPL signals. The metastable helical ribbons show CPL signals (glum =±4.7×10-2 ) at 570 nm. Meanwhile, the nanotubes, which are the thermodynamic products, show intense CPL signals (glum =±5.6×10-2 ) at 610 nm accompanied by helicity inversion. This study provides an efficient way to develop highly dissymmetric CPL nanomaterials by regulating the morphology of metallosupramolecular architectures.

Helicity-driven chiral self-sorting supramolecular polymerization with Ag+: right- and left-helical aggregates.

The study of chiral self-sorting is extremely important for understanding biological systems and for developing applications for the biomedical field. In this study, we attempted unprecedented chiral self-sorting supramolecular polymerization accompanying helical inversion with Ag+ in one enantiomeric component. Bola-type terpyridine-based ligands (R-L1 and S-L1) comprising R- or S-alanine analogs were synthesized. First, R-L1 dissolved in DMSO/H2O (1 : 1, v/v) forms right-handed helical fibers (aggregate I) via supramolecular polymerization. However, after the addition of AgNO3 (0.2-1.1 equiv.) to the R-L1 ligand, in particular, it was found that aggregate II with left-handed helicity is generated from the [R-L1(AgNO3)2] complex through the [R-L1Ag]+ complex via the dissociation of aggregate I by a multistep with an off pathway, thus demonstrating interesting self-sorting properties driven by helicity and shape discrimination. In addition, the [R-L1(AgNO3)2] complex, which acted as a building block to generate aggregate III with a spherical structure, existed as a metastable product during the formation of aggregate II in the presence of 1.2-1.5 equiv. of AgNO3. Furthermore, the AFM and CD results of two samples prepared using aggregates I and III with different volume ratios were similar to those obtained upon the addition of AgNO3 to free R-L1. These findings suggest that homochiral self-sorting in a mixture system occurred by the generation of aggregate II composed of the [R-L1Ag]+ complex via the rearrangement of both, aggregates I and III. This is a unique example of helicity- and shape-driven chiral self-sorting supramolecular polymerization induced by Ag+ starting from one enantiomeric component. This research will improve understanding of homochirality in complex biological models and contribute to the development of new chiral materials and catalysts for asymmetric synthesis.

Metallosupramolecules of Pillar[5]arene with Two Flexible Thiopyridyl Arms: A Heterochiral Cyclic Dimer and Organic Guest-Assisted Homochiral Poly-Pseudo-Rotaxanes.

The formation of a cyclic dimer complex (1) and a poly-pseudo-rotaxane (2) of a racemic A1/A2-thiopyridyl pillar[5]arene (rac-L) with different chirality is reported. A one-pot reaction of rac-L with HgCl2 afforded a heterochiral cyclic dimer complex, [Hg2(pR-L)(pS-L)Cl4]·8CH2Cl2 (1), in which two Hg2+ atoms and one (pR-L)/(pS-L) enantiomeric pair form a [2:2] metallacycle via a metal coordination-based cyclization. Interestingly, the same reaction in the presence of the linear dinitrile guest, CN(CH2)8CN (G), yielded a one-dimensional poly-pseudo-rotaxane, {[Hg(G@pR-L)Cl2][Hg(G@pS-L)Cl2]}n (2), probably due to the rigidified ligand structure resulting from the dinitrile guest (G) threading. In 2, pR-L and pS-L generate two separated homochiral poly-pseudo-rotaxanes in a crystal. Both products are new members of the pillararene-derivative family. This study improves our understanding of self-assembly in nature and leads to this approach being an engineering tool for the construction of mechanically interlocked supramolecules.

In Situ Supramolecular Gel Formed by Cyclohexane Diamine with Aldehyde Derivative.

Low-molecular-weight gels have great potential for use in a variety of fields, including petrochemicals, healthcare, and tissue engineering. These supramolecular gels are frequently metastable, implying that their properties are kinetically controlled to some extent. Here, we report on the in situ supramolecular gel formation by mixing 1,3-cyclohexane diamine (1) and isocyanate derivative (2) without any catalysis at room temperature in various organic solvents. A mixture of building blocks 1 and 2 in various organic solvents, dichloromethane, tetrahydrofuran, chloroform, toluene, and 1,4-dioxane, resulted in the stable formation of supramolecular gel at room temperature within 60-100 s. This gel formation was caused by the generation of urea moieties, which allows for the formation of intermolecular hydrogen-bonding interactions via reactions 1 and 2. In situ supramolecular gels demonstrated a typical entangled fiber structure with a width of 600 nm and a length of several hundred µm. In addition, the supramolecular gels were thermally reversible by heating and cooling. The viscoelastic properties of supramolecular gels in strain and frequency sweets were enhanced by increasing the concentration of a mixed 1 and 2. Furthermore, the supramolecular gels displayed a thixotropic effect, indicating a thermally reversible gel.

Regioisomers of singly bridged calix[6]crown-6 and their heavy alkali metal complexes: a molecular baseball glove for caesium(I).

We report the formation of heavy alkali metal complexes of bicyclic host molecules including the caesium(I) complex that catches the central metal ion with the deep pocket of the host similar to a baseball glove. For this, three regioisomers of singly bridged calix[6]crown-6 [1,2-bridged (H4 L 1,2), 1,3-bridged (H4 L 1,3) and 1,4-bridged (H4 L 1,4)] have been synthesized by alkyl-ation of calix[6]arene with penta-ethyl-ene glycol di-tosyl-ate in the presence of M 2CO3 (M = Na, K, Rb and Cs). The larger the cation size of the metal carbonate, the higher the yield of the H4 L 1,4 isomer, indicating the size-based template effect. A combination of H4 L 1,2 and RbOH allowed isolation of the mononuclear rubidium(I) complex (1) in which the metal center is six-coordinated in a loose fashion, the remaining two oxygen donors in the crown loop and two phenols in the calix rim are uncoordinated. Notably, the complexation of H4 L 1,2 with CsOH yielded the mononuclear caesium(I) complex (2), in which all possible ten binding sites on the deep and good-fit pocket participate in coordination via high cooperativity between the crown loop and calix rim, similar to a baseball glove. In dipolar organic solution, the caesium(I) complex 2 remains intact. H4 L 1,4 afforded a dicesium(I) complex (3) and adjacent complexes are linked by intermolecular cation-π interactions, giving rise to a pseudo one-dimensional coordination polymer. These results provide insight into the metal carbonate-dependent synthesis of calix[6]crowns and the influence of regioisomers on caesium(I) complexation.

Influence of the Reaction Sequence on the Complexation of an NS4-Macrocycle with CdII and CuI Salts Leading to the Formation of Supramolecular Isomers and an Endo/Exocyclic CuI Complex.

In the construction of metallosupramolecules, the reaction sequence in a three-reactant system (one ligand plus two metal ions) could be one of the controlling factors influencing the outcome of the reaction. In this work, the formation of supramolecular isomers (1 and 2) and an endo/exocyclic Cu+ complex (4) of the NS4-macrocycle (L) via different sequential metal addition protocols (routes I-III) is reported. In one-pot reactions of L with Cu(CH3CN)4PF6 in the absence (route I) and presence (route II) of CdI2, a cyclic dimer CuI complex, [Cu2(L)2](PF6)2 (1), and a one-dimensional coordination polymer, [Cu2(L)2]n·n[CdI4] (2), were obtained, respectively. Interestingly, the complex cations in 1 and 2 are supramolecular isomers formed via cyclization and polymerization upon complexation, respectively, probably due to different geometric and electronic complementarities, via the C-H···X- hydrogen bonds, between L and the counterion. In the two-step reaction (route III), an endocyclic Cd2+ complex, [Cd(L)I2] (3), obtained in the first step was utilized in the following reaction with Cu(CH3CN)4PF6, giving rise to an endo/exocyclic tetranuclear Cu+ complex, [Cu4(L)2(CH3CN)6](PF6)4 (4), via Cd2+ → 2Cu+ substitution, which is not accessible by conventional procedures. Solution studies by comparative NMR and electrospray ionization mass spectroscopy also support metal substitution by showing the stronger binding affinity of Cu+ over Cd2+. These results demonstrate that the metal substitution protocol could be useful for reaching novel metallosupramolecules difficult to obtain by other methods.

Construction of 2D Interdigitated Polyrotaxane Layers and their Transformation to a 3D Polyrotaxane by a Photocycloaddition Reaction between Wheels.

Following the pioneering work of Sauvage and Stoddart on rotaxanes, construction of higher dimensional polyrotaxanes in metal-organic frameworks (MOFs) via a modified protocol is challenging. We present the formation of a two-dimensional (2D) polyrotaxane and its conversion to a three-dimensional (3D) polyrotaxane MOF via a photoreaction between interdigitated "olefin wheels". For this purpose, a 2-fold entangled 2D MOF [Pb2(bpp)(sdc)2] (1), showing a 2D + 2D → 2D polyrotaxane motif, has been synthesized from the solvothermal reaction of lead(II) nitrate, 3,3'-stilbenedicarboxylic acid (H2sdc) containing an olefin group, and 1,4-bis(4-pyridyl)piperazine (bpp). The single-crystal X-ray diffraction analysis of 1 revealed that the adjacent entangled 2D layers are interdigitated, with the separation of 3.72 Šbetween C═C bond pairs in adjacent layers satisfying Schmidt's criteria for the occurrence of a [2 + 2] photocycloaddition reaction. Irradiation of the single crystals of 1 under UV light resulted in formation of a 3D polyrotaxane, [Pb2(bpp)(rctt-tccb)]n (2), due to a [2 + 2] photocycloaddition reaction between two wheels via a single-crystal to single-crystal transformation. The photocycloaddition and partial thermal cleavage reaction between 1 and 2 were confirmed by 1H NMR and powder X-ray diffraction (PXRD) in solution and the solid state, respectively. The present approach could contribute to the understanding of the construction of higher dimensional polyrotaxanes which are not accessible by the traditional routes.

Pillar[5]-bis-trithiacrown: Influence of Host-Guest Interactions on the Formation of Coordination Networks.

A pillar[5]-bis-trithiacrown (L) capable of metal binding and organic guest threading simultaneously has been employed, and the influence of dinitrile guests [CN(CH2)nCN (n = 2-6: abbreviated C2-C6)] on the coordination behaviors has been investigated. When the ditopic ligand L was reacted with HgCl2 in the presence of the C2-C6 guests, the shorter guests C2 and C3 afforded a two-dimensional coordination polymer [Hg7Cl14(C2@L)2]n (1) and a one-dimensional coordination polymer [(Hg3Cl6)2(C3@L)2]n (2), respectively. In 1 and 2, each dinitrile guest threads into the pillararene cavity to form a C2@L or C3@L unit via the host-guest interaction. Further linking of these units by exocyclic Hg-S bonds and anion coordination lead to the formation of coordination products with different dimensionalities. While the use of the longer guests C4-C6 under the same reactions yielded a discrete dimercury(II) complex 3, [Hg2Cl4(CH3CN@L)] which contains one acetonitrile solvent molecule because the longer dinitriles do not serve as effective guests. In the NMR and UV-vis studies, the association constants (log K1:1) for the host-guest interactions of L with the dinitrile guests are C2 (4.75) > C3 (4.17) ≫ C4 (2.85) > C5 (2.45) > C6 (too small), indicating that the shorter guests C2 or C3 interact more strongly than longer ones due to the confined interior space of L. Taken collectively, the C2 and C3 guests with proper size-matching promote the formation of coordination polymers and vice versa, suggesting that the guest size could be a controlling factor.

Dynamic Transformation of a Ag+-Coordinated Supramolecular Nanostructure from a 1D Needle to a 1D Helical Tube via a 2D Ribbon Accompanying the Conversion of Complex Structures.

We report a unique dynamic morphology transformation of a Ag+-coordinated supramolecular nanostructure accompanying the conversion of complex structures in aqueous solution. In the presence of AgNO3 (1.0 equiv), the achiral bipyridine-based ligand 1G, possessing hydrazine and glycine moieties, preferentially generated a 1D needle-like structure (nanostructure I) based on the 1GAgNO3 complex (1G:Ag+ = 1:1) as a metastable product. Nanostructure I was then transformed into nanostructure II, which was composed of the 1G3Ag2(NO3)2 complex (1G:Ag+ = 3:2) as the thermodynamically stable product. This nanostructure exhibited a 1D helical tubular structure with a uniform diameter via a 2D ribbon as an intermediator, which led to the generation of a circular dichroism (CD) signal with right-handed (P-type) helicity. The observed dynamic transformation was attributed to formation of the thermodynamically favored helical 1G3Ag2(NO3)2 complex. In addition, the helical 1G3Ag2(NO3)2 complex acted as an initiator in the transformation from the 1D needle-like structure to the 1D helical tube via a 2D ribbon. The enhanced ΔG° value of nanostructure II compared to that of nanostructure I confirmed that nanostructure II is thermodynamically stable. More importantly, the transformation of supramolecular nanostructure I to nanostructure II occurred via an "on" pathway, even though the 1GAgNO3 complex was converted to the 1G3Ag2(NO3)2 complex, which did not involve dissociation from nanostructure I into the monomeric 1GAgNO3 complex species. In the kinetic study, the NO3- anion was found to act as an accelerator for the dynamic transformation from nanostructure I to nanostructure II. This result provides the first example of a dynamic transformation of a 1D needle-like structure into a 1D tubular structure via a 2D ribbon structure, accompanied by the conversion of a complex structure and the generation of a large CD signal for the metallo-supramolecular nanostructure. This study may open up new avenues to the understanding of a dynamic morphology transformation process in biological systems.

Exciplex emissive supramolecular polymer formed by tuning molecular conformation.

We demonstrated the exciplex emission of supramolecular polymers (Bipy-1) possessing bipyridine and pyrene moieties. The distinctive exciplex emission of the supramolecular polymers was controlled by tuning the molecular conformation in different composition ratios of a mixed DMSO/H2O solution. The strong exciplex emission of the supramolecular polymer I with yellow emission was a consequence of the intramolecular charge-transfer interactions in a mixed DMSO/H2O (60 : 40-1 : 99 v/v) solution.

Bispicolyamine-Based Supramolecular Polymeric Gels Induced by Distinct Different Driving Forces with and Without Zn2.

Metal-coordination polymeric gels are interesting areas as organic/inorganic hybrid supramolecular materials. The bispicolylamine (BPA) based gelator (1) showed excellent gelation with typical fibrillar morphology in acetonitrile. Upon complexing 1 with Zn2+, complexes ([1 + Zn + ACN]2+ and [1 + zinc trifluoromethanesulfonate (ZnOTf)]+) with four coordination numbers were formed, which determine the gel structure significantly. A gel-sol transition was induced, driven by the ratio of the two metal complexes produced. Through nuclear magnetic resonance analysis, the driving forces in the gel formation (i.e., hydrogen-bonding and π-π stacking) were observed in detail. In the absence and the presence of Zn2+, the intermolecular hydrogen-bonds and π-π stacking were the primary driving forces in the gel formation, respectively. In addition, the supramolecular gels exhibited a monolayer lamellar structure irrespective of Zn2+. Conclusively, the gels' elasticity and viscosity reduced in the presence of Zn2+.

Pyrene-Based Co-Assembled Supramolecular Gel; Morphology Changes and Macroscale Mechanical Property.

Two pyrene derivatives having the perylenediimide (1) or the alky chain (2) in the middle of molecules were synthesized. Co-assembled supramolecular gels were prepared at different molar ratios of 0.2, 0.5, and 0.8 equiv. of 2 to 1. By SEM observation, the morphology of co-assembled supramolecular gels changed from spherical nanoparticles to three-dimensional network nanofibers as the ratio of 2 increased. In addition, the pyrene-excimer emission of co-assembled gels increased with increasing concentration of 2, and was stronger when compared with the condition without 1 or 2, indicating the formation of pyrene interaction between 1 and 2. In addition, the sol-gel transition was found to be reversible over repeated measurement by tube inversion method. The rheological properties of co-assembled supramolecular gels were also improved by increasing the ratio of 2, due to the increased nanoscale flexibility of supramolecular packing by introducing alkyl chain groups through heterogeneous pyrene interaction. These findings suggest that macroscale mechanical strength of co-assembled supramolecular gel was strongly influenced by nanoscale flexibility of the supramolecular packing.

Formation of a four-bladed waterwheel-type chloro-bridged dicopper(ii) complex with dithiamacrocycle via double exo-coordination.

A combination of O3S2-macrocycles incorporating different sulfur-to-sulfur separations (S-(CH2)n-S, L1: n = 2, L2: n = 3) and copper(ii) nitrate afforded new types of both monocopper(ii) and dicopper(ii) complexes, respectively. L1 gave a 1D coordination polymer [Cu2(L1)2(NO3)4]n (1) based on a convergent exo-coordination mode while L2 resulted in the formation of a divergent exo/exo-coordinated dicopper(ii) complex, [Cu2(L2ox)4(µ-Cl)](NO3)4 (2), whose shape resembles a four-bladed waterwheel in which in situ oxidized macrocycles (L2ox) act as the blades and a CuII-(µ-Cl)-CuII entity corresponds to the axle shaft. The chloro-bridging ligand is derived from the dichloromethane solvent and its arrangement is held together by C-HCl- H-bonds. Compound 2 shows a weak antiferromagnetic property via the CuII-(µ-Cl)-CuII entity.

Finely Controlled Circularly Polarized Luminescence of a Mechano-Responsive Supramolecular Polymer.

Finely controlled circularly polarized luminescence (CPL) supramolecular polymerization based on a tetraphenylethene core with four l- or d-alanine branch side chains (l-1 and d-1) in the solution state is presented, resulting from the tuning of mechanical stimulus. Weak, green emissions of l-1 and d-1 in tetrahydrofuran (THF) were converted into strong blue emissions by tuning the mechanical stimulus. The strong blue emissions were caused by an aggregation-induced emission (AIE) effect during the formation of a supramolecular polymer. Lag time in the supramolecular polymerization was drastically reduced by the mechanical stimulus, which was indicative of the acceleration of the supramolecular polymerization. A significant enhancement of circular dichroism (CD) and CPL signals of l-1 and d-1 was observed by tuning the rotational speed of the mechanical stimulus, implying that the chiral supramolecular polymerization was accelerated by the mechanical stimulus.

Terpyridine-based complex nanofibers with Eu3+ as a highly selective chemical probes for UO22.

Uranyl is a radioactive, toxic pollutant commonly found in the waste remaining after nuclear fuel reprocessing, and it poses several types of risks to human health; therefore, developing absorbents and chemical probes for this compound is crucial to overcoming these issues. This study examined the sensing abilities of terpyridine-appended benzenetricarboxyamide (T-BTA) as a chromogenic probe for detecting uranyl ions (UO22+). The complex with Eu3+ (1-Eu) spontaneously formed nanostructured fibers in H2O owing to the triamide groups of T-BTA, which induced intermolecular hydrogen-bonding interactions. The strong blue emission of these nanofibers in H2O was quenched upon adding UO22+ but not upon adding any other metal ion. This high selectivity was probably because of the interactions between the nitrigen atoms of the terpyridine moieties of 1 and UO22+. Furthermore, the 1-Eu nanofibers assumed spherical morphologies when UO22+ was added. To develop a convenient UO22+ sensor, an electrospun film incorporating 1-Eu (ESF-1-Eu) was manufactured, and it exhibited high selectivity for UO22+ over a variety of rival metal ions. The plot for luminescence change of ESF-1-Eu vs UO22+ concentrations in seawater samples showed a good linearty. Thus, the ESF-1-Eu shows potential as a useful sensor for detecting and removing UO22+ in H2O.