Supercapacitors have emerged as a vital component in electrochemical energy storage, owing to their compelling advantages including high power density, long cycle life, fast charge/discharge capability, wide operating temperature range, high safety, and environmental friendliness. However, the severe self-discharge phenomenon causes spontaneous voltage decay and continuous energy loss under open-circuit conditions, significantly restricting their practical deployment in independent energy storage and long-term reliability scenarios. To address this critical bottleneck, this review first decouples the three dominant self-discharge mechanisms from a fundamental perspective, namely ohmic leakage, parasitic Faradaic reactions, and charge redistribution. Anchored in device architecture, it then systematically summarizes the influence of each component, including the current collector, electrode material, electrolyte, and separator, on self-discharge behavior and the corresponding suppression strategies. This work aims to provide directional guidance for constructing high-energy supercapacitors with ultralow self-discharge.
The [5 + 1] annulation is a highly efficient strategy for constructing six-membered carbocycles, heterocycles, and spiro/fused ring skeletons, playing a crucial role in the synthesis of natural products, pharmaceuticals, and functional molecules. Traditional transition-metal-catalyzed methods often suffer from limitations such as metal contamination, high costs, and tedious workup procedures. In contrast, base-mediated/catalyzed systems have emerged as a prominent research hotspot owing to their metal-free nature, mild conditions, excellent functional group tolerance, and green economy. This review systematically summarizes the recent advances in base-mediated [5 + 1] cycloadditions over the past two decades. Based on the catalytic systems, the reactions are categorized into organic bases (tertiary amines, N-heterocyclic carbenes, organophosphines) and inorganic bases (potassium tert-butoxide, carbonates, and potassium methoxide). The cyclization modes involving various five-atom synthons with one-carbon/one-nitrogen synthons are discussed in detail. This review aims to provide a comprehensive theoretical reference for the future design of novel base-mediated cycloadditions and the construction of complex cyclic pharmaceutical skeletons.
The research of atropisomerism containing aza axes (such as C─N, N─N, C─O, and C─B) in synthetic chemistry has drawn considerable attention in the past few years, primarily due to its importance to natural products total synthesis, pharmaceuticals, and materials science. In contrast to the well-established field of C─C atropisomers, the catalytic asymmetric construction of aza-axial chirality was largely overlooked for a long time until the seminal reports by Taguchi and Curran in the early 2000s. This review mainly summarizes the progress in N-heterocyclic carbene-mediated atroposelective construction of aza-axial chiral atropisomers, covering strategies including kinetic resolution (KR), dynamic KR, desymmetrization, de novo annulation, and direct atroposelective N-acylation. Despite these achievements, the asymmetric synthesis of aza-axial chirality remains far less developed than that of C─C atropisomers, owing to the difficulty in controlling enantioselectivity. Exploration of efficient and novel methods for constructing aza-axial chiral molecules is highly desirable.
This review provides a comprehensive overview of polymers bearing five-membered cyclic carbonate (5CC) moieties, highlighting their role in advancing CO2 utilization and their unique applications based on 5CC moieties. 5CC structures are highly promising due to their unique chemical properties and the fact that their synthesis typically requires milder conditions than most of CO2 conversion processes. The synthetic methodologies are categorized into three primary routes: polymerization of 5CC functional monomers, postpolymerization modification using CO2 or 5CC compounds, and polymerization accompanied by CO2 fixation. While (meth)acrylates are the most extensively developed platform, the exploration of other backbones-including styrene, vinyl ether, siloxane, and cyclic ethers-has realized a diverse array of polymer architectures. Furthermore, this review explores how the distinctive characteristics of 5CC functional polymers-such as high polarity and specific reactivity-lead to various applications, including high-performance adhesives, coatings, energy storage devices, colorimetric sensors, and optical materials. Finally, the current challenges and future perspectives for the development of sustainable, high-functionality 5CC-based materials are addressed.
Lithium-sulfur (Li-S) batteries are promising candidates for energy storage owing to their high theoretical energy density and low cost. However, challenges remain due to inherent issues such as sluggish redox kinetics and the severe polysulfide shuttle effect of the sulfur cathode. It is essential to address these issues without compromising high gravimetric and volumetric energy densities for the commercialization of Li-S batteries. Furthermore, although Li-S batteries perform well at ambient temperatures, achieving reliable operation across wider temperature ranges remains challenging, which is crucial for future mission-specific applications. This review delves into advanced design strategies for sulfur cathodes of Li-S batteries, evaluating their influence on gravimetric energy density (Wh kg-1), volumetric energy density (Wh L-1), and wide-temperature performance. The key parameters of the sulfur cathode significantly relevant to practical application are discussed, including sulfur fraction, sulfur loading, electrolyte-to-sulfur ratio (E/S ratio), and the density of host materials. The aim is to bridge the gap between fundamental research and the practical realization of high-performance Li-S batteries. Finally, the prospects and future research directions toward achieving commercially viable Li-S cells with high-energy density and wide operational temperature capability are discussed.
Growing global energy demands and the continuous depletion of fossil fuel reserves have intensified interest in renewable alternatives, with biomass emerging as a promising carbon-neutral resource. Furfural (FF), a pivotal platform molecule from lignocellulosic biomass, enables the production of diverse value-added chemicals and fuels. Simultaneously, single-atom catalysts (SACs) have attracted major attention in FF valorization due to their isolated active sites, unique electronic structures, and near-complete atom utilization, enabling high activity and selectivity in complex reaction networks. This review summarizes recent advances in SAC-mediated FF upgrading. Significant progress has been made in thermochemical hydrogenation, yielding furfuryl alcohol, tetrahydrofurfuryl alcohol, and cyclopentanone derivatives. SACs have also shown strong performance in hydrogenolysis to produce high-value products such as 2-methylfuran, 2-methyltetrahydrofuran, and tetrahydrofuran. Rapid developments in reductive amination have enabled the selective synthesis of pharmaceutical-relevant amines, including piperidine, particularly using noble-metal SACs. Although less explored, the selective oxidation of FF to furoic acid and other oxygenates is also highlighted. Emerging electro- and photocatalytic FF transformations demonstrate opportunities for integrating renewable electricity or solar energy. Key challenges include improving SAC scalability and stability, tuning coordination environments, and enabling efficient coupling with green-energy inputs such as electrolytic hydrogen.
Iron-based fluorides (FeF3, FeF2) are used as conversion-type cathode materials. With their high theoretical specific capacity, abundant resources, and low cost, they have become promising candidates for next-generation high-energy-density lithium-ion batteries. However, their inherent low electronic and ionic conductivity, significant volume changes, complex phase transition processes, and unstable electrode/electrolyte interfaces severely limit their electrochemical performance and practical applications. This paper provides a systematic review of performance regulation and functionalization design strategies for iron-based fluoride cathode materials in recent years. First, we conduct an in-depth analysis of the distinct lithium storage mechanisms in FeF3 and FeF2, highlighting the resulting performance differences and challenges. Furthermore, we highlight recent research advances in improving charge transport, buffering mechanical stress, suppressing side reactions, and stabilizing interfaces through multilevel strategies. These strategies include nanostructuring and microstructural design, lattice regulation, carbon-based composites, and interface engineering. Through synergistic effects, these strategies effectively enhance the cycling stability, rate capability, and reaction reversibility of iron-based fluorides. Finally, we discuss the key issues facing the future commercialization of iron-based fluorides, aiming to provide design insights for their further development.
Potassium tert-butoxide (KOtBu), a strong non-nucleophilic base with a pKa value of 17.5, has emerged as a versatile and indispensable reagent in modern organic synthesis. Notably, KOtBu can promote a wide range of bond-forming transformations that conventionally rely on transition-metal catalysis, enabling the efficient construction of carbon-carbon (CC), carbon-heteroatom (CX), and heteroatom-heteroatom (XY) bonds under relative mild reaction conditions. KOtBu-mediated reactions predominantly proceed via two well-established mechanistic pathways, namely ionic and radical manifolds, wherein the reactivity of key intermediates is highly dependent on reaction conditions and exogenous additives. Compared to transition-metal catalysts, KOtBu offers prominent advantages in terms of economic cost and environmental compatibility. In this review, we systematically summarize recent advances in KOtBu-involved reactions, covering the construction of carbon-carbon (CC), carbon-nitrogen (including CN and CONH), carbon-oxygen (CO), carbon-silicon (CSi), as well as miscellaneous bonds including carbon-sulfur (CS), carbon-seleno (CSe), carbon-iodo (CI), carbon-deuterium (CD), etc. We focus on reaction development, plausible mechanistic pathways, and potential synthetic applications of these protocols in the synthesis of pharmaceuticals, agrochemicals, and functional materials. This review aims to provide an up-to-date overview of KOtBu-enabled organic transformations for organic, medicinal, and materials chemists, and to facilitate further exploration and expansion of their synthetic utility.
Incorporating graphene quantum dots (GQDs) in 3D printing offers a promising route toward sustainable energy devices. Owing to the interesting optoelectronic properties of GQDs, the performance of 3D-printed energy products is improved: Solar cells gain charge transport enhancement with engineered light-absorbing structures; Batteries increase energy density with optimized porous electrodes, while supercapacitors achieve cycling stability with a precisely engineered network of porosity. Besides conventional applications, this hybridization can lead to innovative, flexible, and integrated energy solutions. Nevertheless, ink stability, large-scale production, and eco-friendly materials remain main concerns. This review discusses the advances made in the application of GQDs for printing inks and their combination with advanced additive manufacturing processes, specifically fused deposition modeling (FDM), direct ink writing (DIW), stereolithography (SLA), and inkjet printing. It is imperative to encourage new strategies around hybrid printing technologies and material design through machine learning toward preparing the field for commercialization. When today's expense and scale dilemmas are solved, GQD-enabled three-dimensional printing will bring forth meaningfully advanced sustainable energy technologies by integrating advanced manufacturing with nanomaterials research. This report also provides a thorough overview of the developments in the field while pointing out future research directions that are necessary for unlocking the potential of this technology.
Anthropogenic activitieshave elevated the concentration of atmospheric CO 2 substantially. This increase has eventually participated to change in climate and global warming. The 1.1% increased of global CO 2 emissions observed in 2023 by reaching a total of 37.4 Gt. Many adsorbents materials were used in previous research but covalent organic frameworks (COFs) have shown significant potential. They are formed by chemically linking organic building blocks into a periodic framework, resulting in an ordered porous crystalline structure with high gas adsorption and retention capacity. COFs possess unique architecture, excellent crystallinity, high surface area, and high porosity which are the ideal condition for a good adsorbents. This review deeplyexplored the application of multidimensional (1‐D, 2‐D, and 3‐D) COFs frameworks for CO 2 adsorption. The CO 2 adsorption capacity of each dimensional class of COFs has been investigated in detail. This review also provides recent research and future direction in this particular field.
Lithium-ion batteries (LIBs), as the most representative energy storage devices, have become deeply integrated into our daily lives. However, the formation of solid electrolyte interphase during the initial cycle consumes a substantial amount of lithium ions (Li+). Moreover, the continuous consumption of Li+ in subsequent cycles further shortens the lifespan of LIBs. To compensate for this irreversible lithium loss, prelithiation technology has attracted substantial attention in recent years and is now recognized as an effective strategy to boost battery performance. Among various prelithiation additives, lithium oxalate (Li2C2O4) stands out as a particularly attractive cathode prelithiation additive, owing to its low cost, excellent air stability, and the absence of solid residual by-products. To date, no systematic review has focused exclusively on Li2C2O4 as a prelithiation additive. In this review, we present a comprehensive overview of the research progress on Li2C2O4, focusing on three critical aspects: delithiation mechanism, modification strategies, and application methods. Furthermore, we discuss future directions and prospects for Li2C2O4, aiming to offer guidance for subsequent research in this field.
Polysilsesquioxanes (PSQs) have been extensively studied as typical organic–inorganic hybrid materials that exhibit functionality and processability owing to organic substituents on silicon atoms, while also thermal and mechanical stability attributable to the inorganic siloxane (Si–O–Si) network structure. We describe herein the introduction of hydrophilic substituents into random PSQs to improve properties, such as water permeability and absorption capability, for developing reverse osmosis (RO) membranes for water separation and antifogging coating materials. Previously studied PSQ‐based RO membranes generally exhibited low water permeability, although they showed excellent heat and chlorine resistance. Recently, we introduced hydroxy‐containing substituents onto the silicon atoms of PSQs, enhancing the water permeability of PSQ‐based RO membranes. Scratch‐resistant antifogging coating materials are obtained by introducing amino, ammonium, and hydroxy units onto PSQ silicon atoms. The low durability of the initially studied materials was improved through chemical modification of the PSQ structures.
Aqueous zinc-ion batteries (AZIBs) are promising for renewable energy storage owing to their intrinsic safety, low cost, and high theoretical capacity. However, zinc metal anodes are intrinsically plagued by dendrite growth, hydrogen evolution reaction, corrosion, surface passivation, and other side reactions, which destabilize the zinc/electrolyte interface. Stabilizing this interface largely depends on the solid electrolyte interphase (SEI). As a naturally formed protective layer on the surface of zinc metal anodes, the SEI not only suffers from the aforementioned issues but also struggles to maintain stability during long-term cycling. Conversely, the artificial SEI enables precise and controllable manipulation of composition, structure, and performance, while integrating multiple functions such as ion-transport modulation and physical-barrier protection, which provides an effective route for overcoming the inherent limitations of natural SEI. Herein, we comprehensively summarize the design principles and key performance parameters of artificial SEI layers, investigate recent research progress in optimization strategies, and analyze current construction approaches, including in situ and ex situ fabrication, as well as compositional classifications, namely inorganic SEI, organic SEI, and organic-inorganic composite SEI. Their advantages, limitations, and interfacial regulation mechanisms are analyzed, and future research directions and challenges are discussed to guide the development of high-performance AZIBs.
The cement industry is responsible for approximately 8% of global anthropogenic CO2 emissions, largely due to the high-temperature calcination of limestone during clinker production. Electrochemical synthesis of calcium hydroxide (Ca(OH)2) has recently emerged as a promising low-carbon alternative that enables limestone decarbonation under near-ambient conditions. This mini review summarizes most recent progress in electrochemical Ca(OH)2 production for low-carbon cement manufacturing. We first outline the foundational electrochemical principles enabling pH-gradient-driven CaCO3 dissolution and Ca(OH)2 precipitation. We then review major technological advances in reactor architecture, electrode and reaction engineering, membrane design, and feedstock diversification, highlighting strategies that significantly reduce cell voltage, mitigate membrane fouling, and enable continuous operation. Representative electrochemical systems and process configurations are systematically compared. Key technical barriers, including Ca(OH)2 production efficiency, membrane stability, energy consumption, and feedstock impurity tolerance, are also analyzed, together with future research priorities such as advanced membrane materials, integrated process design, and AI-assisted optimization. Continued innovation in electrochemical reactor engineering and system integration could enable scalable low-carbon cement production and contribute significantly to industrial decarbonization.
This publication presents the history and key scientific content of Woodward and Hoffmann's publications from 1966 to 1973. It was during the writing of the Angewandte Chemie treatise, published in December 1969, that the Woodward-Hoffmann collaboration became intimate and reached its apex. Highlights in the development of this publication include letters and notes exchanged between Woodward and Hoffmann, excerpts from the drafts of the publications, and early stage, hand drawn chemical graphics. Several figures contain a series of excerpts from Woodward and Hoffmann's drafts that illustrate the evolution of their ideas, text, and chemical pictography.
Heterocyclic N-oxides have become indispensable scaffolds in energetic chemistry, pharmaceuticals, and synthetic organic chemistry. This core scaffold is also present in numerous therapeutic agents, with activities ranging from antimycobacterial and anthelmintic to anti-inflammatory, antioxidant, and anticancer. Over the years, tremendous effort has been devoted to developing efficient synthetic methods starting from simple precursors. Both intermolecular and intramolecular strategies have been widely explored for the construction of cyclic N-oxide derivatives. This review briefly discusses synthetic approaches to the construction of aromatic and aliphatic heterocyclic N-oxides and their derivatives via cyclization reactions from 2011 to 2025. Various synthetic approaches, including inter- and intramolecular cyclization strategies, have been discussed, along with their scope, mechanisms, and limitations. This review not only provides updates on synthetic methods for heterocyclic N-oxide derivatives but also draws the attention of researchers from diverse research fields.
Ethylene and propylene serve as the basic platform chemicals in the chemical industry. Research on their production has garnered significant interest. One of them is the dehydrogenation of light alkanes with the oxidative promotion of CO 2 . This process can simultaneously produce light olefins and achieve resource utilization of CO 2 . Pt‐based catalysts, extensively used in the direct dehydrogenation of light alkanes, are expected to show activity potential in the CO 2 oxidative dehydrogenation (CO 2 ‐ODH) of light alkanes. However, research on Pt‐based catalysts for CO 2 ‐ODH of light alkanes remains limited, and no systematic review has been reported yet. Here, the advancements in Pt‐based catalysts for the CO 2 ‐ODH of ethane and propane are reviewed, including (i) reaction mechanisms, (ii) rational design strategies for efficient and stable Pt‐based catalysts, and (iii) emerging reaction processes and optimization methods. Perspectives on fundamental challenges and future research are proposed. Among them, machine learning‐guided design of Pt‐based catalysts will be an important research direction in the future.
