Search Results (204)

Efficient solubilization of nonpolar substances in polar solvents represents a fundamental challenge in environmental remediation, green chemistry, and separation processes. This limitation stems from the hydrophobic effect, which creates thermodynamic barriers, resulting in low intrinsic solubility and strong phase separation. This review examines the thermodynamic basis of solubilization, focusing on free-energy changes and molecular interaction mechanisms. It discusses various strategies, including surface and interface engineering, host–guest inclusion, solvent engineering, and nanostructure encapsulation, along with their practical applications. Future research directions include smart responsive materials, green solvent design theories, and precise construction of solubilization systems through multi-scale simulations. Full article

Hybrid supramolecular–nanocomposite hydrogels based on polyethylene glycol (PEG), β-cyclodextrin–adamantane host–guest interactions, and silica nanoparticles represent an important class of hierarchical soft materials with tunable viscoelastic and transport properties. This review critically analyzes recent progress in cyclodextrin–silica hybrid PEG hydrogels, focusing on the mechanistic coupling between stiffness, stress relaxation, and molecular transport arising from the interplay between reversible supramolecular crosslinks and nanoparticle-induced confinement effects. Particular attention is given to how host–guest exchange kinetics regulate dynamic bond rearrangement and affinity-mediated retention of hydrophobic cargo, while silica nanoparticles enhance mechanical reinforcement and modify diffusion pathways through tortuosity and interfacial polymer–particle interactions. The analysis highlights how nanoparticle size, loading level, and surface functionalization influence relaxation spectra and network topology, as well as how environmental stimuli may affect supramolecular bond stability and overall material performance. Comparison with alternative inorganic fillers and mesoporous silica architectures further clarifies the specific advantages of silica in achieving balanced mechanical stability and controlled transport behavior. Overall, current evidence indicates that hybrid CD–silica networks enable partial decoupling of stiffness, relaxation dynamics, and diffusion, although complete independence remains constrained by fundamental polymer physics relationships. These insights support the development of predictive structure–property frameworks for advanced biomedical and controlled release applications. Full article

Measurement of material thermodynamic parameters plays a crucial role in understanding the interactions between host materials and guest species. Therefore, developing a general-purpose system for thermodynamic parameter measurement is of great significance. In this work, a complete gas–solid interface thermodynamic parameter measurement platform was developed based on isothermal adsorption and a resonant microcantilever testing platform. Unlike conventional adsorption measurement systems that rely on manual, multi-cycle adsorption–desorption processes, the proposed platform integrates an automated hardware–software architecture together with a stepwise concentration-gradient protocol and on-chip thermal desorption, enabling continuous and efficient acquisition of adsorption isotherms. The study includes: (i) construction of an improved thermodynamic parameter extraction model based on the Sips model, (ii) development of an integrated resonant microcantilever control and acquisition module using a modified Fourier algorithm, and (iii) implementation of an automated testing and data analysis software framework developed in LabVIEW based on the Queued Message Handler (QMH) architecture. The system was validated from both hardware performance and material testing perspectives using CO₂ adsorption on H-SSZ-13 as a representative case. The results show that the system achieves a maximum sampling rate of 10,000 pts (points per second), with minimum root-mean-square (RMS) noise levels of 0.0083 Hz for frequency and 0.0109 °C for temperature. The PID temperature-control settling time (0.1%) is 24.9 ms, and the frequency-response settling time (0.01%) is 9.6 ms. Thermodynamic parameters including entropy change (ΔS), enthalpy change (ΔH), and Gibbs free energy change (ΔG) were successfully extracted during CO₂ adsorption at 294.15 K under different relative uptakes. Reproducibility was verified across three independent samples, yielding a standard deviation of 9.1 J·mol⁻¹ for ΔS at 2% relative uptake and relative standard deviations of 6.85% and 8.12% for ΔH and ΔG, respectively. These results demonstrate that the proposed thermodynamic measurement platform features a simple architecture, superior performance, and high reproducibility in gas–solid interface thermodynamic studies, showing strong potential for future commercialization. Full article

Metal–organic frameworks (MOFs) are unique microporous materials being explored for a wide range of applications. Their porosity and high surface areas can readily be exploited for guest–host interactions, separations, and photochemical catalysis, but many suffer from poor charge separation and fast electron–hole recombination. Introducing structural defects, such as missing linkers or metal nodes, can create unsaturated metal sites and alter band structure, conductivity, and light absorption, improving photocatalytic performance. UiO-66-NH₂ and MIL-125-NH₂ are water-stable, visible-light-absorbing MOFs well suited for photocatalytic degradation of organic dyes. In this work, the influence of defect engineering on photocatalytic properties of MOFs was investigated using formic and acetic acid modulators with UiO-66-NH₂ and variable temperature with MIL-125-NH₂ during synthesis. The resulting materials were characterized by XRD, FTIR and SEM/EDS. Defect states were tracked using N₂ adsorption/BET analysis and UV–Vis spectroscopy. Photocatalytic activity was evaluated by monitoring Rhodamine B (RhB) degradation in aqueous solution under simulated solar irradiation. It was found that increased temperature beyond 120 °C during synthesis promotes mesopore formation and decreases the bandgap in MIL-125-NH₂, resulting in a more photoactive material. Defective MIL-125-NH₂ synthesized at 150 °C showed the most defects and proved to be the best photocatalyst investigated in this study. Formic acid modulation in UiO-66-NH₂ generated smaller crystallites that slightly increased the bandgap; however, the surface area decreased proportionally with the amount of formic acid used. The decreased surface area and observed enhancement in photocatalytic degradation of RhB suggest that formic acid introduces defects into the UiO-66-NH₂ framework that enhance photocatalytic properties. UiO-66-NH₂ treated with acetic acid resulted in larger crystals, increased bandgaps, and increased surface areas, suggesting that acetic acid simply modulates growth rather than imparting defects to the framework. Full article

Allyl isothiocyanate (AITC) is a potent natural antimicrobial agent; however, its practical application is severely hindered by its extreme volatility and pungent, irritating odor. In this study, AITC inclusion complexes (AITC@β-CD) were successfully fabricated via a co-precipitation strategy using β-cyclodextrin (β-CD) as the host matrix. Physicochemical characterizations, including FTIR, SEM, and XRD, confirmed the successful integration of AITC into the β-CD framework, inducing a crystalline phase transition from a cage-type to a channel-type structure. TGA demonstrated a substantial enhancement in thermal stability, with the maximum decomposition temperature shifting to 330 °C. This indicates that the spatial confinement within the channel-type lattice acts as a robust molecular shield that minimizes premature volatilization. Notably, water contact angle measurements revealed that the complexes attained a modulated surface wettability (89.0°), attributed to the structural rearrangement of surface hydroxyl groups. This modification ensures that the material remains compatible with aqueous food matrices while notably masking the unpleasant sensory attributes of pure AITC. Antibacterial assays against the standard indicator strain Escherichia coli (E. coli) confirmed that the encapsulation process preserved the intrinsic bioactivity of the guest, exhibiting comparable inhibitory zones to free AITC. Furthermore, the complexes maintained high inhibitory efficacy against indigenous microbial populations from spoiled fruits. These findings suggest that β-CD encapsulation effectively stabilizes AITC through guest-induced co-crystallization and enhances its consumer acceptability, providing a versatile and efficient strategy for sustainable food preservation. Full article

Conventional electrochemical mechanisms for electrical energy storage face fundamental limitations in achieving ultra-high energy density and high-power output. These constraints arise from the intrinsic nature of the electrochemical processes themselves. Overcoming this challenge requires a paradigm shift—from electrochemical to quantum mechanisms of energy storage. As shown by theoretical models, this concept can be implemented in nanostructured materials consisting of clusters with tunnel-transparent shells. It is possible to build such a structure using supramolecular complexes and clathrate organization of matter. For this purpose, we synthesized a supramolecular clathrate with a hierarchical sub-host<host<guest>> architecture and investigated its conductive and polarization properties using impedance spectroscopy. As shown by the results of the research, in this structure it was possible to combine a high value of the dielectric permittivity with a dielectric loss tangent below unity in the ultra-low-frequency range. This was facilitated by the presumably specific energy structure of the clathrate, as evidenced by the measured spectra of thermally stimulated discharge currents. The ability of the clathrate to accumulate an electric charge is evidenced by the measured hysteresis current-voltage characteristic. The value of the specific capacitance of this clathrate reaches the value that arises from the theoretical model of a quantum supercapacitor. Full article

The widespread occurrence of pharmaceutical residues in aquatic environments necessitates the development of advanced porous materials for efficient remediation. This study investigates the adsorption mechanisms of ibuprofen and atenolol within the high-silica zeolite Y. Batch adsorption experiments demonstrated significant uptake, with loading capacities of 191.6 mg/g for ibuprofen and 273.0 mg/g for atenolol, confirming the material’s effectiveness. Using a combination of neutron and X-ray powder diffraction, complemented by Rietveld refinement and simulated annealing algorithms, we achieved the exact localization of the guest molecules. While the pristine zeolite maintains cubic symmetry $Fd\overline{3}$, the incorporation of pharmaceutical molecules induces significant residual nuclear density and anisotropic lattice distortions. To accurately model these perturbations, a systematic symmetry reduction to the acentric triclinic space group F1 was implemented. This approach enabled an ab initio refinement of the structure, revealing that drug uptake of each guest is governed by distinct chemical drivers. Ibuprofen is stabilized via steric confinement and long-range dispersive interactions. In contrast, atenolol stability is governed by electrostatic charge compensation within the zeolitic voids. Our results suggest that the final adsorption geometry is dictated by the spatial orientation of functional groups and host–guest proximity rather than molecular chirality. These results provide a microscopic model describing the fundamental host–guest interactions in FAU zeolites. This structural understanding is an essential step towards the potential use of zeolitic materials in environmental remediation and complex guest sequestration. Full article

The development of nanoscale chiral materials with enhanced optical properties holds significant promise for advancing technologies in light-emitting devices and enantioselective sensing. Here, we report the self-assembly of chiral metal–organic cages from an axially chiral, AIE-active binaphthyl dicarboxylate ligand. This supramolecular architecture functions as a multifunctional platform, demonstrating a high affinity for anionic guests through synergistic electrostatic and hydrogen-bonding interactions. The rigid cage framework not only enhances the ligand’s intrinsic aggregation-induced emission (AIE) but also serves as a highly effective chiral amplifier. Notably, MOCs significantly boost the circularly polarized luminescence (CPL), achieving a luminescence dissymmetry factor (|g_lum|) of 1.2 × 10⁻³. This value represents an approximately five-fold enhancement over that of the unassembled ligand. The photophysical properties of this chiral supramolecular system provide a strategic blueprint for designing next-generation optical nanomaterials. Full article

The escalating prevalence of counterfeiting and forgery has imposed unprecedented demands on advanced anti-counterfeiting technologies. Traditional luminescent materials, relying on single-mode or static emission, are inherently vulnerable to replication using commercially available phosphors or simple spectral blending. Multimode luminescent materials exhibiting excitation wavelength-dependent emission offer significantly higher encoding capacity and forgery resistance. Herein, we report the colloidal synthesis of lanthanide-doped Cs₂ZrCl₆ nanocrystals (Ln³⁺ = Tb, Eu, Pr, Sm, Dy, Ho) via a robust hot-injection route. These nanocrystals universally exhibit efficient host-to-guest energy transfer from self-trapped excitons (STEs) under 254 nm, yielding sharp characteristic Ln³⁺ f–f emission alongside the intrinsic broadband STE luminescence. Critically, Tb³⁺ enables direct 4f → 5d excitation at ~275 nm, while Eu³⁺ introduces a low-energy Eu³⁺ ← Cl⁻ LMCT band at ~305 nm, completely bypassing STE emission. Due to their multimode luminescent characteristics, we fabricate a triple-mode anti-counterfeiting label displaying different colors under different types of excitation. These findings establish a breakthrough excitation-encoded multimode platform, offering potential applications for next-generation photonic security labels, scintillation detectors, and solid-state lighting applications. Full article

The application of microsphere molecularly imprinted materials for the targeted extraction and purification of flavonoids derived from agricultural waste has emerged as a prominent area of investigation. An innovative boronate affinity imprinted microsphere (MC-CD@BA-MIP) was successfully synthesized using the Pickering emulsion interfacial assembly strategy for the selective separation of naringin (NRG). The double-bond functionalized covalent organic framework (COF)-based microspheres were synthesized through Schiff–base reaction and secondary interfacial emulsion polymerization. Then, the synthetic mono-(6-mercapto-6-deoxy)-β-cyclodextrin (SH-β-CD) was grafted onto the surface of the microspheres (MC) using click chemistry. The 1-allylpyridine-3-boronic acid (APBA) as a functional monomer was grafted onto the initiator (ABIB) through atom transfer radical polymerization (ATRP). Ultimately, the synthesized boronic acid-imprinted ABIB-BA-MIPs were immobilized onto the COFs microsphere surface through host–guest interactions. As expected, under neutral conditions, the MC-CD@BA-MIPs still exhibited a significant adsorption capacity (38.78 μmol g⁻¹ at 308 K) for NRG. The regenerated MC-CD@BA-MIPs maintained 92.56% of their initial adsorption capacity through six consecutive cycles. Full article

Non-covalent and dynamic covalent interactions enable supramolecular systems to function as adaptive platforms in biomedical research, offering novel strategies for precision medicine applications. This review examines five-year developments in supramolecular applications across precision medical domains, including disease diagnosis, bioimaging, targeted drug delivery, tissue engineering, and gene therapy. The review begins by systematically categorizing supramolecular structures into dynamic covalent systems (e.g., disulfide bonds, boronate esters, and hydrazone bonds) and dynamic non-covalent systems (e.g., host–guest interactions, hydrogen-bond networks, metal coordination, and π–π stacking), highlighting current strategies employed to optimize their responsiveness, stability, and targeting efficiency. Representative case studies, such as cyclodextrin-based nanocarriers and metal–organic frameworks (MOFs), are thoroughly analyzed to illustrate how supramolecular systems can enhance precision in drug delivery and improve biocompatibility. Furthermore, this article critically discusses major challenges faced during clinical translation, encompassing structural instability, inadequate specificity of environmental responsiveness, pharmacokinetic and toxicity concerns, and difficulties in scalable manufacturing. Potential future directions to overcome these barriers are proposed, emphasizing biomimetic interface engineering and dynamic crosslinking strategies. Collectively, the continued evolution in structural optimization and functional integration within supramolecular systems holds great promise for achieving personalized diagnostic and therapeutic platforms, thereby accelerating their translation into clinical practice and profoundly shaping the future landscape of precision medicine. Full article

Macrocyclic arenes are rich-electron macrocycles bridged by methylene or methyl groups from aromatic rings substituted by hydroxyl or alkoxy groups. It has attracted great interest in host–guest chemistry and supramolecular self-assembly due to its clear cavity, adjustable structure and multifunctional binding ability. In particular, nitrogen-containing macrocyclic arenes including (hetero) aromatic moieties—constructed from building blocks such as pyrrole, carbazole, phenothiazine, and imidazole—have undergone rapid development, yielding a new generation of functional macrocycles, including calix[4]carbazoles, Tröger’s base-derived macrocycles, and phenothiazine-based architectures. These nitrogen-functionalized macrocycles feature rich chemical derivatization potential, unique structural and host–guest characteristics, and exceptional photophysical properties. They show great promise in molecular recognition, selective adsorption and separation, and the development of advanced functional materials. This review summarizes recent advances in the design, synthesis, and application of nitrogen-containing macrocyclic arenes, with a particular focus on structure–property relationships and emerging functions. Full article

Traditional petroleum engineering materials have problems such as single functionality and poor environmental adaptability in terms of lost circulation control and enhanced oil recovery. Supramolecular gels, with their dynamic reversible non-covalent network structure, demonstrate unique advantages in this regard. This paper classifies supramolecular gels into hydrogen bond type, metal coordination type, host–guest type, and electrostatic interaction type based on differences in crosslinking structures. It explains the construction principles and characteristics of each type of gel and analyses their application progress in petroleum engineering fields, such as lost circulation control in drilling, temporary plugging in fracturing, and profile control in enhanced oil recovery. It also discusses the advantages and disadvantages of different systems and future development directions. Research has shown that the molecular design strategy of supramolecular gels can effectively address technical challenges under complex conditions, offering new insights for oil and gas field development. Further optimization of their long-term stability and large-scale production technology is needed to advance their practical application. Full article

Solid–liquid phase change materials (PCMs) have attracted significant attention due to their high enthalpy, which enables superior energy storage density. However, it is difficult to maintain their original shapes in a molten state. Therefore, confining PCMs within porous materials is an important method, either through mixing molten polymers and PCMs or confining PCMs in pre-prepared porous materials (e.g., aerogels). The former method is straightforward and easy to execute but its stability is severely limited, and the latter is exactly the opposite. Herein, aerogel-confined functional liquid made via in situ solid–liquid host–guest composite strategy is reported. As a proof of concept, Nylon 66 and 1,6-hexanediol are selected as the solid and liquid phases, respectively. 1,6-hexanediol not only serves as a solvent to dissolve Nylon 66 but also induces sol–gel transition during the cooling process and acts as a PCM to store energy. Unlike aerogel-supported systems requiring multi-step processing, this approach integrates porous host formation and PCM encapsulation in one step. The resulting shape-stabilized PCMs (ss-PCMs) exhibit obscure leakage, high latent heat (160 J/g), mechanical robustness (compressive modulus of 3.6 MPa), and low thermal conductivity (0.081 W/(m·K)) above 75 wt% loading of 1,6-hexanediol. These ss-PCMs enable infrared stealth by delaying thermal detection and passive thermal buffering that suppress temperature fluctuations. The in situ solid–liquid host–guest composite strategy is straightforward, being achievable through a one-pot method involving heating and cooling cycles, with high raw material utilization and minimal waste generation, thus maximizing the conversion rate of raw materials into the final product. By combining the excellent liquid retention capability of aerogels with process simplicity, this methodology opens new avenues for the development of ss-PCMs. Full article

In this study, we systematically investigated the adsorption behavior of a titanium-based metal–organic framework (MOF) sensing layer on five primary alcohol homologs using the quartz crystal microbalance (QCM) technique. Unexpectedly, response signals were significantly enhanced for molecules exceeding the framework’s pore dimensions, contradicting conventional molecular sieving models. Further investigations revealed that the adsorption time constant (${\tau }_a$) is linearly proportional to the molecular diameter ($R^2=0.952$) and the integral response (AUC) increases almost exponentially with the molecular weight ($R^2=0.891$). Although the effective diffusion coefficient ($D_{\mathrm{eff}}$) decreases with increasing molecular size ($D_{\mathrm{eff}}\propto d^{-5.96}$, $R^2=0.981$), the normalized diffusion hindrance ratio ($D_{\mathrm{eff}}/D_{\mathrm{gas}}$) decreases logarithmically with an increasing diameter. Larger responses result from stronger host–guest interactions with the framework despite significant diffusion limitations for larger molecules. These findings demonstrate the synergistic regulation of adsorption and diffusion in MOF-QCM systems. Our investigation experimentally elucidates the ’size-selectivity paradox’ in microporous sensing interfaces and establishes a quantitative framework for optimizing sensor performance through balanced control of diffusion kinetics and interfacial interactions in similar materials. Full article