Chiral triarylmethane skeleton is an important structural unit of many known compounds that are widely applied in organic functional materials and pharmaceuticals. Thus, the efficient construction of this class of compounds has attracted intensive attention from chemists. There are two main difficulties in synthesizing this type of compound: (i) the steric resistance of molecular structures would make it hard to be constructed; (ii) there are three similar aryl groups on the stereocenter, which is difficult to achieve stereo-identification. At present, the most common strategy is to introduce the third aryl group into a diarylmethane framework through the asymmetric Friedel-Crafts reaction or addition reaction of electron-rich arenes, so as to construct chiral triarylmethanes. In this review, we summarized the recent developments in the construction of various chiral triarylmethanes and chiral tetraarylmethanes from easily accessible compounds under organocatalytic conditions. This article describes based on the types of electrophilic reagents, mainly including quinone methides, indole imine methides, and azadienes. At the same time, we also emphasize the mechanism of each representative reaction, which might enlighten the future development of this field.

Aqueous organic redox flow battery (AORFB) is regarded as the most promising next-generation technology for energy storage that stores electricity in redox-active organics lysed in mild salt-electrolytes. Composed of abundant elements such as C, H, O, and N, the adapted organics have a high degree of structural diversity and tunability, endowing it possible to modulate the physicochemical properties of water solubility, redox potential, and stability, and resulting in potential cost-effectiveness, ecological and environmental safety. Therefore, the designable organics consumedly expand the distance for exceeding battery behaviors in comparison with the inorganic counterparts. Herein, this study presents an overview of pH-neutral AORFBs that employ nonflammable water-soluble molecules with cheap inorganic salts as supporting electrolytes. Particular emphasis is given to the progress of molecular engineering design and synthesis of non-viologen-based organic anolytes and their respective AORFB performance. Additionally, some comments on present opportunities and perspectives of this ascendant domain are also demonstrated.

The construction of d₃-methylated all-carbon quaternary stereocenters has been successfully developed via carbene-catalyzed desymmetrization of prochiral d₃-methylated oxindolyl 1,3-diketones. Three new stereogenic centers were efficiently constructed with satisfactory outcomes. Diverse spiro-polycyclic molecules with a d₃-methylated all-carbon quaternary stereocenter were generated in good to excellent yields with good to excellent diastereoselectivities and excellent enantioselectivities. This reaction features a broad substrate scope, good functional-group tolerance, and easy scale-up.

The enantioselective construction of chiral 6-(indole-2-yl)-3,4-dihydropyran-2-one skeleton was demonstrated by the formal [3 + 3] cycloaddition reaction of α-bromocinnamaldehyde with β-ketoester indole catalyzed by chiral N-heterocyclic carbene (NHC). The reaction proceeds smoothly via a vinyl acyl azolium intermediate (electron-poor enone) generated from NHC-aldehyde adducts, providing 6-(indole-2-yl)-3,4-dihydropyran-2-one derivatives in good yields with excellent enantioselectivities (up to 98% ee).

Two-dimensional mesoporous materials (2DMMs) refer to thin two-dimensional (2D) nanosheets with randomly dispersed or ordered mesopores, which can combine the advantages of 2D materials and mesoporous materials while overcoming their inherent drawbacks, leading to enhanced application performance. A self-assembly strategy has been recognized as a promising manufacturing method for 2DMMs with customized performance. Over the past decades, encouraging progress has been made in the development of 2DMMs via the self-assembly strategy with a variety of compositions, morphologies, mesoporous structures, and pore sizes. Here, we provide a comprehensive review on recent progress in the fabrication of 2DMMs through this strategy, focusing on the synthesis methods, including molecular self-assembly methods, single micelle assembly methods, multi-templates methods, surface-limited co-assembly methods, and template-free methods. In addition, we set out the challenges faced by 2DMMs in future research and point out potential development directions.

Zeolite nanosheets with shortened diffusion paths and high external surface areas have drawn significant attention. This unique morphology of zeolites can endow them with reduced diffusion resistance and high accessibility of active sites, and thereby good catalytic performance. Exploring simple synthesis strategies for zeolite nanosheets is mostly desired in zeolite chemistry. Herein, MFI zeolite nanosheets with a thickness of 50-100 nm along the b-axis and a length of 1 μm along the c-axis, namely zeolite macro-nanosheets, have been successfully synthesized via the strategy of combining pre-aging and pH regulation without the use of complex templates/additives and fluorine media. Pre-aging at a relatively high temperature of 90 °C and low alkalinity for crystallization (pH = 7.0~8.5) are found to play key roles in controlling macro-nanosheet synthesis, which can promote the formation of MFI zeolite precursors and then dissociate them into smaller ones for the following oriented aggregation during hydrothermal treatment. Crystallization kinetic studies suggest that the two-dimensional crystal growth is the intrinsic behavior of zeolite crystallization under employed conditions. This synthesis strategy can be easily extended to the synthesis of heteroatom-containing MFI macro-nanosheets, such as ZSM-5 and TS-1.

Nickel-catalyzed reductive cross-coupling (RCC) reactions using two carbon electrophiles as coupling partners provide one of the most reliable and straightforward protocols for facile construction of valuable C-C bonds in the realm of organic chemistry. In recent years, significant progress has been made in the methodological developments and mechanistic studies of these reactions. This review summarizes four widely accepted mechanisms for RCC reactions that have been proposed by experiments or density functional theory calculations. The major difference between these four types of mechanisms lies in the oxidation state of the active catalyst, the change in the valence of nickel during the catalytic cycle, the involvement of carbon radicals, and the form in which the radicals are present. Herein, we focus on covering representative advancements in experimental and theoretical mechanistic studies, aiming to offer vital mechanistic insights into key intermediates, reaction rates, the activation modes of electrophiles, rate- or selectivity-determining steps, and the origin of the cross-selectivity.

Room-temperature Na-S batteries with Al current collectors face the long-standing challenges of poor cycling performance and rate capability due to the serious sodium polysulfides (NaPSs) shuttling and sluggish reaction kinetics. Here, we demonstrate that a high-performance and low-cost quasi-Na-S battery can be realized by using the Cu@carbon nanotube (CNT) cathode host and unconventional Cu current collector (Cu-CC) in an ether electrolyte. Detailed ex-situ characterizations reveal that the Cu@CNT/S was transformed to NaPSs anchoring on Cu₇S₄ nanocrystals (~11 nm) during the cycling, forming the NaPS@Cu₇S₄/CNT cathode with robust sulfur immobilization and enhanced Na⁺ reaction kinetics. Moreover, the chemical interaction between NaPSs and Cu-CC in situ creates a robust Cu-CC/electrode interface with ultra-small resistance (< 4 Ω), greatly improving the electrode stability and charge transfer kinetics. The synergy of efficient NaPSs trapping and favorable Cu/electrode interface endows the quasi-Na-S battery with a moderate discharge plateau (around 1.2~1.75 V), excellent rate capability (396.9 mAh g^-1 at 10 A g^-1), and ultra-stable cycling performance (nearly no capacity decay over 1190 cycles). These features make it quite suitable for stable and cost-sensitive grid-scale applications.

Alkaline water electrolysis has a large industrial application and development potential in hydrogen energy owing to its high maturity and low cost. However, its moderate energy efficiency, especially caused by bubble effects, inhibits its use for large-scale hydrogen production. To overcome this shortcoming, this review first analyzes the bubble effect and summarizes the external operation methods, such as external field intensification, flow operation, fluctuation operation, and surfactant addition to the electrolyte, to enhance bubble separation in the electrolyzer. Then, electrode and flow channel structure optimization, particularly superhydrophilic and superaerophobic electrodes, and flow channels with varying heights, square column arrangements, and inlet/outlet numbers are highlighted. Finally, future research directions in alkaline water electrolysis technology are suggested to advance the industrial application of large-scale alkaline water electrolysis.

In-situ transmission electron microscopy (TEM) enables direct observation of the micromorphology and microstructure evolution of catalysts in the chemical atmosphere. Studying the structural evolution during the formation of molybdenum carbide using in-situ TEM is helpful for the preparation of high-performance carbide catalysts. Herein, the formation mechanism of porous Mo₂C from MoO₂ nanoparticles (NPs) was studied by in-situ TEM. The formation of Mo₂C was induced by the defects of MoO₂, and the formed Mo₂C facilitated the carbonization of neighboring MoO₂ NPs. The growth rate of Mo₂C between MoO₂ NPs was slower compared to that within a single MoO₂ NP. In addition, the formation and growth of pores in Mo₂C were also studied; the pores grew radially during the early stages from the nucleation sites and later grew branched and curved. As Mo₂C underwent competitive growth, the pores transitioned from straight to curved. Eventually, during prolonged carbonization at high temperatures, Mo₂C underwent sintering.

Decacarbonyldimanganese (Mn₂(CO)₁₀), one of the most long-standing organometallic reagents, bears a weak Mn-Mn bond, which occurs a homo-cleavage feasibly under heating or light-irritation, delivering an active manganese-centered radical. This highly reactive metallic radical could activate the Si-H bond, C-halogen bond, N-halogen bond, S-halogen bond, and O=O bond, generating corresponding Mn species and Si, C, N, S, and O radicals. This wonderful reactivity enables an extensive utilization of this dimeric manganese in catalytic atom-transfer reactions and oxidation reactions. In this review, we offer a comprehensive review of this growing area in recent decades. Critical comparisons and mechanism analyses are provided, along with personal perspectives for future studies.

Overall water splitting is considered as an effective technique for hydrogen (H₂) production; however, it usually requires large operating voltage mainly due to the high equilibrium potential of the anodic oxygen evolution reaction (OER). Replacing OER with energy-saving anode reactions not only reduces the operating voltage for H₂ production but also generates high-value-added chemicals or purifies wastewater. This review article provides an overview of the fundamental reaction principles of overall water splitting and typical energy-saving alternative anode reactions, including methanol oxidation, hydrazine oxidation, and urea oxidation reactions. Then, the preparation methods, regulation strategies, and composition/structure-performance relations of advanced catalysts for these energy-efficient H₂ generation technologies are discussed. Finally, we propose the underlying challenges and perspectives for this promising field.

The thermally induced transitions between low-spin (LS) and high-spin (HS) configurations of spin-crossover (SCO) nanoparticles are simulated, focusing on the effects of localized surface and bulk interactions on the average magnetization of 2D square lattices. The thermal behaviors and hysteresis cycles are investigated within the framework of the Ising model Hamiltonian and are conducted following two approaches: local mean field approximation (LMFA) and Monte Carlo entropic sampling (MCES) techniques. The results obtained by these two methods are compared for the two square lattice sizes, 6 $$ \times $$ 6 and 7 $$ \times $$ 7. Thus, when the bulk-surface interaction term is set to zero, the two approaches lead to identical values of the surface and bulk transition temperatures separated by a long intermediate plateau in both cases. Although hysteresis curves exhibit a similar shape, LMFA shows slightly larger widths $$ \Delta T $$ than MCES. On increasing bulk-surface interaction term, the two methods lead to different shifts in equilibrium temperature values for both bulk and surface components, respectively, to lower and higher values by MCES. In general, it is found that LMFA shifts surface equilibrium temperature differently to lower values and enhances the hysteresis effect, particularly for surface molecules. On the other hand, for the 7 $$ \times $$ 7 square lattice, the equilibrium temperatures are slightly higher by 1.5% and 3.2% for bulk and surface molecules, respectively, with a narrower hysteresis width in the surface. Moreover, with the MCES method, an abrupt transition instead of a hysteresis transition is calculated for surface molecules ($$ \Delta T_{surf}^{MCES}=0 $$ K).

Two-dimensional (2D) materials have garnered much interest due to their exceptional optical, electrical, and mechanical properties. Strain engineering, as a crucial approach to modulate the physicochemical characteristics of 2D materials, has been widely used in various fields, especially for energy storage and conversion. Herein, the recent progress in strain engineering of 2D materials is summarized for energy storage and conversion applications. The fundamental understanding of strain in 2D materials is first described. Then, some synthetic methods for modulating the properties of 2D materials via strain engineering are introduced. Further, the applications of strain engineering of 2D materials in energy storage, photocatalysis, and electrocatalysis are discussed. Finally, the challenges and perspectives on strain engineering of 2D materials are also outlined.