Self‐Assembled α‐Cyanostilbenes for Advanced Functional Materials

In the specific context of condensed media, the significant and increasing recent interest in the α‐cyanostilbene (CS) motif [? Ar? CH?C(CN)? Ar? ] is relevant. These compounds have shown remarkable optical features in addition to interesting electrical properties, and hence they are recognized as very suitable and versatile options for the development of functional materials. This progress report is focused on current and future use of CS structures and molecular assemblies with the aim of exploring and developing for the next generations of functional materials. A critical selection of illustrative materials that contain the CS motif, including relevant subfamilies such as the dicyanodistyrylbenzene and 2,3,3‐triphenylacrylonitrile shows how, driven by the self‐assembly of CS blocks, a variety of properties, effects, and possibilities for practical applications can be offered to the scientific community, through different rational routes for the elaboration of advanced materials. A survey is provided on the research efforts directed toward promoting the self‐assembly of the solid state (polycrystalline solids, thin films, and single crystals), liquid crystals, nanostructures, and gels with multistimuli responsiveness, and applications for sensors, organic light‐emitting diodes, organic field effect transistors, organic lasers, solar cells, or bioimaging purposes.     

K2MnAl11O19六铝酸盐催化剂的制备及其催化甲烷燃烧性能的研究

采用共沉淀法、溶胶-凝胶法和反相微乳液法制备六铝酸盐催化剂K2MnAl11O19,利用XRD、BET和TG-DTA技术及甲烷燃烧活性对催化剂进行了表征和活性验证。结果表明,3种方法所制备催化剂经1200℃焙烧4h后均可以形成完整的六铝酸盐晶型,同时都具有高的催化性能和高温稳定性,其中反相微乳液法制备的K2MnAl11O19催化剂具有较高的比表面积和甲烷催化燃烧活性,起燃温度T10%=458℃,至676℃(T90%)甲烷完全转化。     

Self‐Assembled Biomimetic Capsules for Self‐Preservation

The inorganic semiconductor is an attractive material in sewage disposal and solar power generation. The main challenges associated with environment‐sensitive semiconductors are structural degradation and deactivation caused by the unfavorable environment. Here, inspired by the pomegranate, a self‐protection strategy based on the self‐assembly of silver chloride (AgCl) particles is reported. The distributed photosensitive AgCl particles can be encapsulated by themselves through mixing aqueous silver nitrate and protic ionic liquids (PILs). A probable assembling mechanism is proposed based on the electrostatic potential investigation of PILs cations. The AgCl particles inside the shell maintain their morphology and structure well after 6 months light‐treatment. Moreover, they exhibit excellent photocatalytic activity, same as newly prepared AgCl particles, for degradation of methyl orange (MO), neutral red (NR), bromocresol green (BG), rhodamine B (RhB), Congo red (CR), and crystal violet (CV).     

Self‐Organized Multiconstituent Catalytic Nanomotors

Self‐organized catalytic nanomotors consisting of more than one individual component are presented. Tadpole‐like catalytic nanomotors fabricated by dynamic shadowing growth (DSG) self‐organize randomly to form two‐nanomotor clusters (≈1–3% yield) that spin as opposed to circular motion exhibited by the individual structures. By introducing magnetic materials to another system, self‐assembled “helicopter” nanomotors consisting of a V‐shaped nanomotor and a microbead are formed with ≈25% yield, showing a significantly higher yield than the control (0%). A flexible swimmer system that performs complex swimming, such as maneuvering around stationary objects, is also presented. These nanomotor systems are inherently more complex than those previously studied and may be the next step towards building sophisticated multifunctional nanomachinery systems.     

Fluorescent Nanoparticles Based on Self‐Assembled π‐Conjugated Systems

π‐Conjugated molecules are interesting components to prepare fluorescent nanoparticles. From the use of polymer chains that form small aggregates in water to the self‐assembly of small chromophoric segments into highly ordered structures, the preparation of these materials allows to develop systems with applications as sensors or biolabels. The potential functionalization of the nanoparticles can lead to specific probing. This progress report describes the recent advances in the preparation of such emittive organic nanoparticles.     

Self‐Assembled Ag‐MXA Superclusters with Structure‐Dependent Mechanical Properties

The low elastic modulus and time‐consuming formation process represent the major challenges that impede the penetration of nanoparticle superstructures into daily life applications. As observed in the molecular or atomic crystals, more effective interactions between adjacent nanoparticles would introduce beneficial features to assemblies enabling optimized mechanical properties. Here, a straightforward synthetic strategy is showed that allows fast and scalable fabrication of 2D Ag‐mercaptoalkyl acid superclusters of either hexagonal or lamellar topology. Remarkably, these ordered superstructures exhibit a structure‐dependent elastic modulus which is subject to the tether length of straight‐chain mercaptoalkyl acids or the ratio between silver and tether molecules. These superclusters are plastic and moldable against arbitrarily shaped masters of macroscopic dimensions, thereby opening a wealth of possibilities to develop more nanocrystals with practically useful nanoscopic properties.     

Self‐Assembled Peptide–Polyoxometalate Hybrid Nanospheres: Two in One Enhances Targeted Inhibition of Amyloid β‐Peptide Aggregation Associated with Alzheimer's Disease

Amyloid fibril formation is a critical step in Alzheimer's disease (AD) pathogenesis. Inhibition of Aβ aggregation has shown promising against AD and has been used in clinic trials. Here, a novel strategy is reported for the self‐assembly of polyoxometalate–peptide (POM@P) hybrid particles as bifunctional Aβ inhibitors. The two‐in‐one bifunctional POM@P nanoparticles show an enhanced inhibition effect on amyloid aggregation in mice cerebrospinal fluid. Incorporating a clinically used Aβ fibril‐staining dye, congo red (CR), into the hybrid colloidal spheres, the nanoparticles can also act as an effective fluorescent probe to monitor the inhibition process of POM@P via CR fluorescence change in real time. It is believed that such flexible organic–inorganic hybrid systems may prompt the design of new multifunctional materials for AD treatment.     

Guest Encapsulation within Surface‐Adsorbed Self‐Assembled Cages

Coordination cages encapsulate a wide variety of guests in the solution state. This ability renders them useful for applications such as catalysis and the sequestration of precious materials. A simple and general method for the immobilization of coordination cages on alumina is reported. Cage loadings are quantified via adsorption isotherms and guest displacement assays demonstrate that the adsorbed cages retain the ability to encapsulate and separate guest and non‐guest molecules. Finally, a system of two cages, adsorbed on to different regions of alumina, stabilizes and separates a pair of Diels–Alder reagents. The addition of a single competitive guest results in the controlled release of the reagents, thus triggering their reaction. This method of coordination cage immobilization on solid phases is envisaged to be applicable to the extensive library of reported cages, enabling new applications based upon selective solid‐phase molecular encapsulation.     

Self‐Assembled Peptide‐Based Nanomaterials for Biomedical Imaging and Therapy

Peptide‐based materials are one of the most important biomaterials, with diverse structures and functionalities. Over the past few decades, a self‐assembly strategy is introduced to construct peptide‐based nanomaterials, which can form well‐controlled superstructures with high stability and multivalent effect. More recently, peptide‐based functional biomaterials are widely utilized in clinical applications. However, there is no comprehensive review article that summarizes this growing area, from fundamental research to clinic translation. In this review, the recent progress of peptide‐based materials, from molecular building block peptides and self‐assembly driving forces, to biomedical and clinical applications is systematically summarized. Ex situ and in situ constructed nanomaterials based on functional peptides are presented. The advantages of intelligent in situ construction of peptide‐based nanomaterials in vivo are emphasized, including construction strategy, nanostructure modulation, and biomedical effects. This review highlights the importance of self‐assembled peptide nanostructures for nanomedicine and can facilitate further knowledge and understanding of these nanosystems toward clinical translation.