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Solution phase room‐temperature phosphorescence (RTP) from organic phosphors is seldom realized. Herein we report one of the highest quantum yield solution state RTP (ca. 41.8 %) in water, from a structurally simple phthalimide phosphor, by employing an organic–inorganic supramolecular scaffolding strategy. We further use these supramolecular hybrid phosphors as a light‐harvesting scaffold to achieve delayed fluorescence from orthogonally anchored Sulforhodamine acceptor dyes via an efficient triplet to singlet Förster resonance energy transfer (TS‐FRET), which is rarely achieved in solution. Electrostatic cross‐linking of the inorganic scaffold at higher concentrations further facilitates the formation of self‐standing hydrogels with efficient RTP and energy‐transfer mediated long‐lived fluorescence. [ABSTRACT FROM AUTHOR]

Synthesis of supramolecular block copolymers (BCPs) from small monomers has been recently attempted. However, the lack of dispersity and length control of the blocky segments limits its functional outcome. Herein we demonstrate the synthesis of well-defined supramolecular BCPs with tunable block lengths by varying the monomer to seed ratio in a kinetically controlled seeded supramolecular polymerization process. Structured Illumination microscopy (SIM) and spectroscopic analyses provide structural characterization of these supramolecular BCPs, which offers various possibilities as axial organic heterostructures. [ABSTRACT FROM AUTHOR]

Fuel‐regulated self‐assembly is a key principle by which Nature creates spatiotemporally controlled materials and dynamic molecular systems that are in continuous communication (molecular exchange) with the external environment. Designing artificial materials that self‐assemble and disassemble via conversion/consumption of a chemical fuel is a grand challenge in supramolecular chemistry, which requires a profound knowledge of the factors governing these complex systems. Here we focus on recently reported metal‐coordinated monomers that polymerise in the presence of ATP and depolymerise upon ATP hydrolysis, exploring their fuel‐regulated self‐assembly/disassembly via multiscale molecular modelling. We use all‐atom simulations to assess the role of ATP in stabilising these monomers in assemblies, and we then build on a minimalistic model to investigate their fuel‐driven polymerisation and depolymerisation on a higher scale. In this way, we elucidate general aspects of fuel‐regulated self‐assembly that are important toward the rational design of new types of bioinspired materials. [ABSTRACT FROM AUTHOR]

Adenosine triphosphate (ATP) is a molecular unit of energy that drives various processes in the cellular environment. In this Minireview, we discuss the potential of physical and chemical properties of ATP for the development of bio‐inspired, synthetic ATP‐induced supramolecular systems with dynamic, stimuli‐responsive and active assembly characteristics. Molecular design rules for ATP‐induced assemblies with various architectures and their stimuli‐responsive structural and functional response are categorized. Special attention is given to the immense potential of ATP‐fuelled designs in the nascent field of transient/non‐equilibrium supramolecular polymerization for the synthesis of lifelike temporally programmable soft materials. Finally, the existing dearth and fate of ATP‐driven systems for future challenges are discussed. [ABSTRACT FROM AUTHOR]

Transient supramolecular self‐assembly has evolved as a tool to create temporally programmable smart materials. Yet, so far single‐component self‐assembly has been mostly explored. In contrast, multicomponent self‐assembly provides an opportunity to create unique nanostructures exhibiting complex functional outcomes, newer and different than individual components. Even two‐component can result in multiple organizations, such as self‐sorted domains or co‐assembled heterostructures, can occur, thus making it highly complex to predict and reversibly modulate these microstructures. In this study, we attempted to create active bicomponent nanoparticle assemblies of orthogonally pH‐responsive‐group‐functionalized gold and cadmium selenide nanoparticles with temporal microstructural control on their composition (self‐sorted or co‐assembly) in order to harvest their emergent transient photocatalytic activity by coupling to temporal changes in pH. Moving towards multicomponent systems can deliver next level control in terms of structural and functional outcomes of supramolecular systems. [ABSTRACT FROM AUTHOR]

Dissipative systems, that constantly consume energy for sustenance, are ubiquitous and essential to life. In synthetic systems, the phenomenon promises emergent properties and different structure from the ones existing at thermodynamic equilibrium. It can create reconfigurable and temporally programmable life‐like smart materials. In this study, we attempt to create reconfigurable, temporally programmable self‐assembly using the redox chemistry of a core‐substituted naphthalene diimide derivative. As a result, transient reconfiguration of supramolecular assembly from vesicle to sheet along with transient fluorescence switching with fuel‐dependent lifetime is attained. We believe that such a design strategy can advance the synthesis of active, adaptive and autonomous materials. [ABSTRACT FROM AUTHOR]

van der Waals heterostructures formed by 2D materials have attracted much attention in the last few years. Recently, 2D nanosheets linked by covalent bonds have been found to exhibit novel properties. In the present study we have investigated supramolecular layered heterostructures formed by nanosheets of MoS2 with BC7N, g‐C3N4 and graphene. These materials have been synthesized via a non‐covalent host–guest synthetic design using cucurbit[8]uril (CB[8]) hosts. In addition to offering reversible disassembly, these heterostructures show good visible‐light‐driven hydrogen evolution reaction (HER) activity as well as reasonable gas adsorption and other properties. [ABSTRACT FROM AUTHOR]

Ambient solution and amorphous state room temperature phosphorescence (RTP) from purely organic chromophores is rarely achieved. Remarkable stabilization of triplet excitons is realized to obtain deep red phosphorescence in water and in amorphous film state under ambient conditions by a unique supramolecular hybrid assembly between inorganic laponite clay and heavy atom core substituted naphthalene diimide (NDI) phosphor. Structural rigidity and oxygen tolerance of the inorganic template along with controlled molecular organization via supramolecular scaffolding are envisaged to alleviate the unprecedented aqueous phase phosphorescence. Aqueous phosphorescence: An unprecedented organic‐inorganic hybrid co‐assembly approach is proposed to obtain aqueous state as well as amorphous red‐emitting room temperature phosphorescence. Heavy‐atom effect in the NDI derivative along with its J‐aggregation enhance the intersystem crossing efficiency whereas rigid and oxygen tolerant laponite templates stabilize the triplets. [ABSTRACT FROM AUTHOR]

Temporal control of supramolecular assemblies to modulate the structural and transient characteristics of synthetic nanostructures is an active field of research within supramolecular chemistry. Molecular designs to attain temporal control have often taken inspiration from biological assemblies. One such assembly in Nature which has been studied extensively, for its well-defined structure and programmable self-assembly, is the ATP-driven seeded self-assembly of actin. Here we show, in a synthetic manifestation of actin self-assembly, an ATP-selective and ATP-fuelled, controlled supramolecular polymerization of a phosphate receptor functionalised monomer. It undergoes fuel-driven nucleation and seeded growth that provide length control and narrow dispersity of the resultant assemblies. Furthermore, coupling via ATP-hydrolysing enzymes yielded its transient characteristics. These results will usher investigations into synthetic analogues of important biological self-assembly motifs and will prove to be a significant advancement toward biomimetic temporally programmed materials. [ABSTRACT FROM AUTHOR]

Chirality-driven self-sorting is envisaged to efficiently control functional properties in supramolecular materials. However, the challenge arises because of a lack of analytical methods to directly monitor the enantioselectivity of the resulting supramolecular assemblies. Presented herein are two fluorescent core-substituted naphthalene-diimide-based donor and acceptor molecules with minimal structural mismatch and they comprise strong self-recognizing chiral motifs to determine the self-sorting process. As a consequence, stereoselective supramolecular polymerization with an unprecedented chirality control over energy transfer has been achieved. This chirality-controlled energy transfer has been further exploited as an efficient probe to visualize microscopically the chirality driven self-sorting. [ABSTRACT FROM AUTHOR]

Synthetic manifestations of supramolecular chirality have extensively drawn inspiration from naturally occurring systems. Even though in biological systems conformational changes are dissipative, synthetic systems that change conformation under non-equilibrium conditions have still not been established. Herein, we attempt to alleviate this scenario by reporting a synthetic supramolecular system that undergoes temporal changes in its helical conformation as an active system at the expense of a biologically relevant chemical fuel, ATP. Use of enzymes working in tandem provides transient and switchable helices with modular lifetime and stereomutation rates. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we explore the use of supramolecular nanofibers as an electrolyte for in‐plane micro‐supercapacitors. The supramolecular nanofibers obtained from the self‐assembly of donor–acceptor (D‐A) molecules, coronene tetracarboxylate salt (CS) and dodecyl methyl viologen (DMV), carrying positive and negative ionic charges, respectively, were drop‐coated onto metal gap electrodes using an aqueous dispersion to form the device. Under dry conditions (<35 % relative humidity, RH), the device exhibited a stack capacitance of 160 F cm−3 with energy and power densities comparable to high‐performance micro‐supercapacitors. Although the electrolyte has aqueous origin, in dry conditions, it is capable of operating in a voltage window of 0–3 V. This supramolecular micro‐supercapacitor device (micro‐SS) was fabricated only with metal electrodes without using electrode material in it, thanks to the ability of the nanofiber to provide extended surface area for charge storage. The 1D face‐to‐face arrangement of D‐A molecules seems to provide an efficient pathway for the diffusion of ions across the electrodes. The present study not only provides a new approach to obtain an ambient stable electrolyte with wide operating voltage window but also gives a low‐cost method of fabricating micro‐supercapacitors with reasonably high energy and power densities. [ABSTRACT FROM AUTHOR]

A 'chirality driven self-sorting' strategy is introduced for the controlled supramolecular organization of donor (D) and acceptor (A) molecules in multicomponent assemblies. The trans-1,2-bis(amido)cyclohexane ( trans-BAC) has been identified as a supramolecular motif with strong homochiral recognition to direct this chirality controlled assembly process of enantiomers in solution. Stereoselective supramolecular polymerization of trans-BAC appended naphthalene diimide monomers (NDIs) has been probed in detail by spectroscopic and mechanistic investigations. This chirality-driven self-sorting design of enantiomeric components also offers to realize mixed and segregated D-A stacks by supramolecular co-assembly of the NDI acceptors with trans-BAC appended dialkoxynaphthalene (DAN) donor monomers. Such an unprecedented chirality control on D-A organization paves the way for the creation of supramolecular p-n nanostructures with controlled molecular-level organization. [ABSTRACT FROM AUTHOR]

Several covalent strategies towards surface charge-reversal in nanochannels have been reported with the purpose of manipulating ion transport. However, covalent routes lack dynamism, modularity and post-synthetic flexibility, and hence restrict their applicability in different environments. Here, we introduce a facile non-covalent approach towards charge-reversal in nanochannels (<10 nm) using strong charge-transfer interactions between dicationic viologen (acceptor) and trianionic pyranine (donor). The polarity of ion transport was switched from anion selective to ambipolar to cation selective by controlling the extent of viologen bound to the pyranine. We could also regulate the ion transport with respect to pH by selecting a donor with pH-responsive functional groups. The modularity of this approach further allows facile integration of various functional groups capable of responding to stimuli such as light and temperature to modulate the transport of ions as well as molecules. [ABSTRACT FROM AUTHOR]

Flexible and dynamic porous coordination polymers (PCPs) with well-defined nanospaces composed of chromophoric organic linkers provide a scaffold for encapsulation of versatile guest molecules through noncovalent interactions. PCPs thus provide a potential platform for molecular recognition. Herein, we report a flexible 3D supramolecular framework {[Zn(ndc)( o-phen)]⋅DMF} n ( o-phen=1,10-phenanthroline, ndc=2,6-napthalenedicarboxylate) with confined nanospaces that can accommodate different electron-donating aromatic amine guests with selective turn-on emission signaling. This system serves as a molecular recognition platform through an emission-readout process. Such unprecedented tunable emission with different amines is attributed to its emissive charge-transfer (CT) complexation with o-phen linkers. In certain cases this CT emission is further amplified by energy transfer from the chromophoric linker unit ndc, as evidenced by single-crystal X-ray structural characterization. [ABSTRACT FROM AUTHOR]

Self-assembly of carbonate linkage bearing naphthalene diimides (NDI) showed unusually red-shifted excimer emission at approximately 560 nm. On the other hand, the ether linkers showed usual excimers at around 520 nm, highlighting the role of the carbonate group in tuning the molecular organization and the resultant photophysical properties of NDI. [ABSTRACT FROM AUTHOR]

Stereoselective noncovalent synthesis of one-dimensional helical self-assembled stacks of achiral oligo(p-phenylenevinylene) ureidotriazine (AOPV3) monomers is obtained by a chiral supramolecular auxiliary approach. The racemic mixture of helical stacks of achiral AOPV3 molecules is converted into homochiral helical stacks, as shown by both spectroscopic measurements and molecular modeling simulations. The conversion is promoted by an orthogonal two-point ion-pair interaction with the chiral auxiliary dibenzoyl tartaric acid (d- or l-TA) molecules, which biases the angle population distribution and thereby the stack helicity. The induced preferred helicity is maintained by the OPV stacks even after the removal of the chiral auxiliary by extraction with ethylenediamine (EDA), due to the kinetic stability of the OPV stacks at room temperature. Spectroscopic probing of the helical self-assembly and the racemization process of these π-conjugated OPV chromophores shed further light into the mechanistic pathways of this chiral asymmetric noncovalent synthesis and the kinetic stability of the stacks produced. The racemization of the stacks follows first-order kinetics and no switch in mechanism is observed as a result of a temperature change; therefore, a racemization via disassembly assembly is proposed. Remarkably, the preferred helicity of the stacks of achiral AOPV3 can be retained almost completely after a heating-cooling cycle where the stacks first partially depolymerize and then polymerize again with the still existing stacks being the seeds for self-assembly of achiral AOPV3. Only after a fully dissociated state is obtained at high temperatures, the optical activity of the supramolecular stack self-assembled at room temperature is lost. [ABSTRACT FROM AUTHOR]

Self-assembled nanotapes of a few tailor-made oligo(p-phenylenevinylene)s (OPVs) have been prepared and used as supramolecular donor scaffold to study the fluorescence resonance energy transfer (FRET) to a suitable acceptor. In nonpolar solvents, FRET occurs with nearly 63-81% efficiency, exclusively from the self-assembled OPVs to entrapped Rhodamine B, resulting in the quenching of the donor emission with concomitant formation of the acceptor emission at 625 nm. The efficiency of FRET is considerably influenced by the ability of the OPVs to form the self-assembled aggregates and hence could be controlled by structural variation of the molecules, and polarity of the solvent. Most importantly, FRET could be controlled by temperature as a result of the thermally reversible self-assembly process. The FRET efficiency was significantly enhanced (Ca. 90%) in a xerogel film of the OPV1 which is dispersed with relatively less amount of the acceptor (33 mol %), when compared to that of the aggregates in dodecane gel. FRET is not efficient in polar solvents due to weak self-organization of the chromophores. These results indicate that energy transfer occurs exclusively from the self-assembled donor and not directly from the individual donor molecules. The present study illustrates that the self-assembly of chromophores facilitates temperature and solvent controlled FRET within π-conjugated nanostructures. [ABSTRACT FROM AUTHOR]

A non-covalent, amphiphilic foldamer design leads to an efficient charge-transfer complex between dipyrene (donor) and naphthalene diimide (acceptor) derivatives, which further self-assembles into one-dimensional nanofibers with an alternate (mixed) donor–acceptor arrangement. [ABSTRACT FROM AUTHOR]

Preferred handedness in the supramolecular chirality of self-assembled achiral oligo(p-phenylenevinylene) (OPV) derivatives is induced by chiral solvents and spectroscopic probing provides insight into the mechanistic aspects of this chiral induction through chiral solvation. [ABSTRACT FROM AUTHOR]

The article discusses the concept of amphiphilicity in the advancement in supramolecular chemistry which regain through hydrophobic amphiphiles of molecules. It highlights the use of various techniques to observe alkyl shells including neutron scattering measurements, small-angle X-ray and cryo-transmission electron microscopy. It also cites the benefits of liquid crystallinity for a long-range order in the manipulation of nanometre scale in materials with a monolithic structure.

Noncovalent synthesis of stable heterostructures (graphene-BN, MoS2-graphene) of layered materials has been accomplished by a ternary host-guest complex as a heterocomplementary supramolecular motif. Besides being reversible, this supramolecular strategy to generate heterostructures may find uses in many situations. [ABSTRACT FROM AUTHOR]

An achiral oligo(p-phenylene vinylene) derivative with a ureido-triazine hydrogen bonding unit self-assembles into rows of hydrogen bonded dimers at the liquid/solid interface. Scanning tunneling microscopy reveals the formation of chiral domains, but overall, the surface remains racemic. Addition of a chiral auxiliary which is able to interact with the dimers through hydrogen bonding, showed that global organizational chirality could be achieved since a majority of the domains show the same handedness. After removing the chiral auxiliary with a volatile solvent, the global organizational chirality could be trapped, revealing a memory effect. With this straightforward supramolecular approach, we were able to create a chiral surface with preferred handedness composed of achiral molecules at the air/solid interface. [ABSTRACT FROM AUTHOR]

Natural systems have been an inspiration to synthetic supramolecular chemistry. Synthetic demonstrations of dissipative biological systems such as actin filaments are a formidable scientific challenge in attaining future life-like materials. Dynamic instability of such structures beckons control of self-organization in the temporal regimes. In this study, we present a fuel-dependent helical assembly of a supramolecular polymer. We further attempt the synthetic manifestation of a temporally programmable self-assembly. Additionally, the fuel-induced chiral (re)organization with the employment of various enzymes singularly and in tandem have resulted in designing a multistate transient self-assembly. These parameter modulations result in controllable lifetimes and rates. We thus report, for the first time, a temporally programmed multistate reorganization of self-assembly. [ABSTRACT FROM AUTHOR]

We introduce a non-covalent pore engineering approach to achieve exceptional reversibility of functionalization in SBA-15 through viologen–pyranine charge transfer (CT) modules. By employing alkyl derivatives of pyranine as donors, we could exploit the strong CT interactions between pyranine and viologen to reversibly modify the pore size and philicity. The fast binding of the donors enables quick and facile functionalization within minutes at room temperature. The modularity of the approach enables modification of pores with custom-designed compositions, components, and functions. The high selectivity exhibited by viologen on the pore wall facilitated its use in a CT affinity column. [ABSTRACT FROM AUTHOR]