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Owing to the intrinsic complexity of crystallization and the heterogeneity of precursors, the specific stages and corresponding behaviors of an actual crystallization system remain ambiguous, which makes the univariate-controlled crystallization-kinetics-regulated synthesis and design of zeolite morphology and porosity an unrealized blueprint. In this study, a facile and univariate modulation (i.e., OH^-/SiO₂) strategy was developed to regulate zeolite crystallization kinetics, and zeolite L mesocrystals were synthesized rapidly (within 1-2 h) with almost all LTL morphologies (from cylindrical or disc-like shapes to nanoclusters or nanocrystals) in the simplest SiO₂-Al₂O₃-K₂O-H₂O system. Using time-resolved analysis of the change in the solid-liquid Si/Al nutrient and crystallinity evolution, the intertwined and complex crystallization processes of zeolite L were clearly distinguished into four distinct stages: induction, nucleation, growth, and ripening. Under alkalinity-controlled conditions, the reactivity, Si/Al distribution, and state of aluminosilicates were critical to the formation of short-range order in the amorphous matrix, which greatly influenced the nucleation frequency and assembly state. Subsequently, these nucleation differences evoked correspondingly different kinetic growth behaviors. A putative alkalinity-controlled nonclassical crystallization mechanism was uncovered, and its validity was evaluated by analyzing morphology evolution, NH₄F etching, and the effects of modifiers. Furthermore, adsorption tests demonstrated the high adsorption capacity of a series of zeolite L for guest molecules with various sizes and properties (e.g., gaseous aromatic hydrocarbon, aqueous dye, and protein). LESS      Full article

The emission of CO₂ has become an increasingly prominent issue. Electrochemical reduction of CO₂ to value-added chemicals provides a promising strategy to mitigate energy shortage and achieve carbon neutrality. Two-dimensional (2D) materials are highly attractive for the fabrication of catalysts owing to their special electronic and geometric properties as well as a multitude of edge active sites. Various 2D materials have been proposed for synthesis and use in the conversion of CO₂ to versatile carbonous products. This review presents the latest progress on various 2D materials with a focus on their synthesis and applications in the electrochemical reduction of CO₂. Initially, the advantages of 2D materials for CO₂ electro-reduction are briefly discussed. Subsequently, common methods for the synthesis of 2D materials and the role of these materials in the electrochemical reduction of CO₂ are elaborated. Finally, some perspectives for future investigations of 2D materials for CO₂ electro-reduction are proposed. LESS      Full article

A novel supramolecular self-assembly nanostructure of porous helical nanoribbons (PHNRs) was developed. PHNRs from oligoaniline derivatives were fabricated through the chemical oxidation of aniline in an i-propanol/water mixture as mediated by β-cyclodextrin (β-CD). The role of β-CD was considered vital through the modulation of the addition time point of β-CD and the molar ratio of β-CD/aniline. In addition, at the early stage of polymerization, the host-guest complex between oligoaniline and β-CD was formed, which was involved in the initial supramolecular assembly process. However, with the reorganization of the oligoaniline assemblies during the polymerization time, the abscission of β-CD from the helical nanoribbons was observed, which eventually induced the formation of PHNRs. We believe the supramolecular host-modulated assembly strategy presented herein will be instructive for the fabrication of porous supramolecular nanostructures. LESS      Full article

The enantioselective 1,1-diarylation of allyl sulfones and vinyl sulfones is reported for the first time, enabled by a combination of Pd₂dba₃ and a chiral SPINOL-derived phosphoric acid. Various chiral sulfones containing 1,1-diarylalkane motifs were obtained in moderate to good yields with moderate to high enantioselectivities. Control experiments suggested that the sulfone group plays a key role in providing enantioselectivity and reactivity control and might serve as a directing group. LESS      Full article

Sodium metal batteries (SMBs), benefiting from their low cost and high energy densities, have drawn considerable interest as large-scale energy storage devices. However, uncontrollable dendritic formation of sodium metal anodes (SMAs) caused by inhomogeneous deposition of Na⁺ severely decreases the Coulombic efficiency, leads to short cycling life, and poses potential safety hazards, dragging SMBs out of practical applications. Electrolytes are attracting massive attention for not only providing ion transport channels but also exhibiting vital effects on interfacial compatibility and dendrite growth. In fact, the as-formed solid electrolyte interphase (SEI) has a great influence on the deposition and stripping process of SMAs. Moreover, Na plating process is accompanied by the generation of SEI, in which the electrolyte plays a vital role. Nevertheless, until now, the interaction among electrolyte-SEI-sodium dendrite has rarely been summarized. Herein, a fundamental understanding of sodium dendrite is concluded and the influence of the electrolyte and interface on Na⁺ deposition is emphasized. Furthermore, the outlook for constructing dendrite-inhibited SMAs is suggested. LESS      Full article

Herein, we propose a versatile “functional modular assembly” strategy for customizing MOFs that allows installing the desired functional unit into a host material. The functional unit could be switched according to different applications. MOF-808, a highly stable Zr-MOF containing dangling formate groups, was selected as a host material for demonstration. Functional molecules with carboxyl connectors can be directly inserted into MOF-808 to form functional modular MOFs (FM-MOFs) through single substitution, while for those without carboxyl connectors, a pre-designed convertor was grafted firstly followed by the functional molecules in a stepwise manner. A series of tailor-made FM-MOFs were generated and show excellent performance toward different applications, such as adsorption, catalysis, fluorescent sensing, electrochemistry, and the control of surface wettability. On the other hand, the functional units on the FM-MOFs can switch freely and completely via full interconversion, as well as partly to construct multivariate MOFs (MTV-MOFs). Therefore, this strategy provides a benchmark for rapid customization of functional MOFs for diverse applications that can realize the rapid modular design of materials. LESS      Full article

Volatile Organic Compounds (VOCs) are known to be hazardous and harmful to human health and the environment. In mixtures or during repeated exposures, significant toxicity of these compounds in trace amounts has been revealed. In vitro air-liquid interface approaches underlined the interest in evaluating the impact of repeated VOC exposure and the importance of carrying out a toxicological validation of the techniques in addition to the standard chemical analyses. The difficulties in sampling and measuring VOCs in stationary source emissions are due to both the complexity of the mixture present and the wide range of concentrations. The coupling of VOC treatment techniques results in efficient systems with lower operating energy consumption. Three main couplings are outlined in this review, highlighting their advantages and relevance. First, adsorption-catalysis coupling is particularly valuable by using adsorption and catalytic oxidation regeneration initiated, for example, by selective dielectric heating. Then, several key aspects of the plasma catalysis process, such as the choice of catalysts suitable for the non-thermal plasma (NTP) environment, the simultaneous removal of different VOCs, and the in situ regeneration of the catalyst by NTP exposure, are discussed. The adsorption-photocatalysis coupling technology is also one of the effective and promising methods for VOC removal. The VOC molecules strongly adsorbed on the surface of the photocatalyst can be directly oxidized by the photogenerated hole on the photocatalyst (e.g., TiO₂). LESS      Full article

In recent years, fluorescent supramolecular materials have received significant attention due to their wide application prospects. However, the relationship between the conformation of supramolecules and their photophysical properties remains an open question. In this study, two rhomboidal metallacycle isomers, SA and SB, self-assembled with trans- and cis-isomers of tetraphenylethylene-based ditopic pyridyl ligands (LA and LB), and a 120° di-platinum (II) acceptor were prepared. Compared with metallacycle SB constructed by cis- tetraphenylethylene (TPE)-based ligand LB, the curved rhomboidal metallacycle SA constructed with trans-TPE-based ligand LA can restrict molecular motions of the aromatic groups on TPE and exhibits better light-emitting properties. Moreover, curved SA also exhibited better fluorescence stability than isomer SB towards molecules with strongly electron-withdrawing groups. This work provides a new platform to explore the relationship between conformation and the corresponding photophysical properties. LESS      Full article