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Hydrogen peroxide (H2O2) is identified as a promising reagent for fuel cells, reducing the dependency on carbon‐based fuels. In this work, electrochemically synthesized polymers are employed to improve the efficiency of the oxygen (O2) reduction reaction, thus producing H2O2 in an environmentally friendly way. Two aminoanthraquinones, as well as riboflavin (vitamin B2), are successfully immobilized via oxidative electropolymerization onto both glassy carbon and carbon paper. Of the investigated compounds, polyriboflavin shows a high Faradaic efficiency toward O2 reduction, even at a very low potential of only −0.1 V versus SHE. This catalytic effect is present in neutral and alkaline conditions, using both glassy carbon and carbon paper, but highly pronounced in neutral, aqueous solutions. [ABSTRACT FROM AUTHOR]

A simple, environmentally friendly and efficient montmorillonite (MMT)‐metal ion (Me: Mg2+, Ca2+, Fe3+ and Zn2+)‐carboxymethyl cellulose (CMC) organic–inorganic hybrid film is successfully applied to flame retardant cellulose paper through layer‐by‐layer self‐assembly (LbL) technology. Using SEM, TGA, XPS, air permeability test and horizontal flammability test to characterize its surface morphology, thermal stability, air permeability and flame retardancy. The results show that MMT‐Me‐CMC system can endow cellulose paper with high flame retardancy properties, and different metal ions have different contributions to the flame retardancy. MMT with multi‐layer structure and high specific surface area is beneficial to reduce the air permeability of paper, thereby effectively reducing the flammability of flammable pyrolysis gas and the transfer of heat. The XPS analysis shows that the Zn2+ flame retardant system promotes the formation of graphitized char in the condensed phase. Meanwhile, the possible flame‐retardant mechanism of the system is clarified. Zn2+ replaces Al3+ in MMT, thus increasing the active acidic catalytic sites on MMT. This promotes the carbonization of degradation products and forms graphitized clay‐rich char. This work provides a simple and efficient LbL preparation strategy and provides a reference for the catalytic role of metal ions in the flame retardancy of cellulose paper. [ABSTRACT FROM AUTHOR]

The commercialization of Li−S batteries is seriously hindered by polysulfides with severe shuttle effect, and the inherent insulating properties and slow reaction kinetics of insoluble Li2S products. Transition metal sulfides (TMSs) have a high adsorption capacity for polysulfides and have been shown to have a strong catalytic effect on polysulfide conversion reactions. This paper reviews the research on the application of Unary TMSs, heterostructures, etc. in Li−S batteries, and gives some research methods for TMD catalysts in Li−S batteries. Finally, it points out the main focuses and direction of future Li−S battery research and development. It aims to provide some insights into the design and manufacture of advanced Li−S batteries for commercial use. [ABSTRACT FROM AUTHOR]

A high-flux beamline optimized for non-resonant X-ray emission spectroscopy (XES) in the tender X-ray energy range has been constructed at the BESSY II synchrotron source. The beamline utilizes a cryogenically cooled undulator that provides X-rays over the energy range 2.1 keV to 9.5 keV. This energy range provides access to XES [and in the future X-ray absorption spectroscopy (XAS)] studies of transition metals ranging from Ti to Cu (Kα, Kβ lines) and Zr to Ag (Lα, Lβ), as well as light elements including P, S, Cl, K and Ca (Kα, Kβ). The beamline can be operated in two modes. In PINK mode, a multilayer monochromator (E/ΔE ≃ 30-80) provides a high photon flux (1014 photons s-1 at 6 keV and 300 mA ring current), allowing non-resonant XES measurements of dilute substances. This mode is currently available for general user operation. X-ray absorption near-edge structure and resonant XAS techniques will be available after the second stage of the PINK commissioning, when a high monochromatic mode (E/ΔE ≃ 10000-40000) will be facilitated by a double-crystal monochromator. At present, the beamline incorporates two von Hamos spectrometers, enabling time-resolved XES experiments with time scales down to 0.1 s and the possibility of two-color XES experiments. This paper describes the optical scheme of the PINK beamline and the endstation. The design of the two von Hamos dispersive spectrometers and sample environment are discussed here in detail. To illustrate, XES spectra of phosphorus complexes, KCl, TiO2 and Co3O4 measured using the PINK setup are presented. [ABSTRACT FROM AUTHOR]

Organic‐chemical literature encompasses large numbers of catalysts and reactions they can effect. Many of these examples are published merely to document the catalysts' scope but do not necessarily guarantee that a given catalyst is "optimal"—in terms of yield or enantiomeric excess—for a particular reaction. This paper describes a Machine Learning model that aims to improve such catalyst‐reaction assignments based on the carefully curated literature data. As we show here for the case of asymmetric magnesium catalysis, this model achieves relatively high accuracy and offers out of‐the‐box predictions successfully validated by experiment, e.g. in synthetically demanding asymmetric reductions or Michael additions. [ABSTRACT FROM AUTHOR]

This paper presents the results of the use of MFI zeolite as a catalyst modified with tin and iron. Sn‐MFI and Fe‐MFI catalysts were obtained by ion exchange under hydrothermal conditions with and without ammonium exchange. Catalytic materials were characterized with the use of analytical techniques such as X‐ray diffraction (XRD), Brunauer–Emmett–Teller method (BET), diffuse reflectance spectroscopy in the ultraviolet‐visible range (DRS UV–visible), hydrogen temperature programmed reduction (H2‐TPR), or Fourier transform infrared (FTIR) spectroscopy. The one‐pot catalytic conversion of fructose was performed at 220 °C for 1–5 h. Based on the results, the influence of time and material selection on the products obtained can be seen. Lactic acid (LAC) was obtained with a yield of 68.7% (after 2 h) and levulinic acid (LA) with a yield of 70.9% (after 5 h) with the participation of MFI. In turn, formic acid with a yield of 28.5% (after 5 h) was obtained with the participation of Fe‐MFI. [ABSTRACT FROM AUTHOR]

Nitrogenases are the only enzymes that activate the strong triple bond in N2. The mechanism for the activation has been very difficult to determine in spite of decades of work. In previous modeling studies it has been suggested that the mechanism for nitrogen activation starts out by four pre‐activation steps (A0–A4) before catalysis. That suggestion led to excellent agreement with experimental Elecrtron Paramagnetic Resonance (EPR) observations in the step where N2 becomes protonated (E4). An important part of the pre‐activation is that a sulfide is released. In the present paper, the details of the pre‐activation are modeled, including the release of the sulfide. Several possible transition states for the release have been obtained. An A4(E0) state is reached which is very similar to the E4 state. For completeness, the steps going back from A4(E0) to A0 after catalysis are also modeled, including the insertion of a sulfide. [ABSTRACT FROM AUTHOR]

Allenes represent a distinctive class of organic molecules characterized by their unique physical and chemical properties. Among them, chiral allenes play a significant role in modern chemistry. They not only serve as pivotal frameworks for natural products and drug molecules but also are essential building blocks in organic synthesis. Over the years, numerous remarkable and efficient methods have been developed for the synthesis of chiral allenes. Notably, the catalytic synthesis of chiral allenes using transition metals in conjunction with chiral ligands has garnered considerable attention. This review paper aims to provide an overview of recent advancements in the synthesis of chiral allenes through asymmetric 1,4‐difunctionalization of 1,3‐enynes, in which two distinct strategies including non‐radical and radical processes are highlighted. [ABSTRACT FROM AUTHOR]

Graphene, a remarkable material known for its exceptional properties, can be efficiently produced through environmentally friendly methods using renewable resources and eco‐friendly solvents. Recent studies have highlighted the potential of leaf extracts as effective reducing and stabilizing agents in converting graphene oxide (GO) to graphene. This paper presents a green and cost‐effective approach for the effective deposition of silver nanoparticles (Ag NPs) onto the reduced graphene oxide (RGO) nanosheets. The process involves the co‐reduction of GO and AgNO3 in water using Moringa olifera leaf extract, resulting in the formation of a nanocomposite termed reduced graphene oxide‐silver (Ag‐RGO). The formation of RGO and Ag NP is confirmed through UV‐visible spectroscopy, XRD, and Raman spectroscopy techniques. TEM images revealed the morphology of the nanocomposite, depicting 2‐dimensional graphene sheets adorned with Ag NPs. FT‐IR analysis confirmed the removal of oxygenated functional groups from GO, indicating graphene formation. The synthesized Ag‐RGO nanocomposite exhibited significant catalytic, antioxidant, and electrochemical properties. This study underscores the utilization of natural ingredients as sustainable alternatives for producing multifunctional graphene‐silver nanocomposites. [ABSTRACT FROM AUTHOR]

Transposition reactions, i. e. switching the position of functional groups, are a powerful tool for molecular editing. The transposition of a halogen atom attached to an aromatic ring, referred to as the halogen dance reaction, has great potential in the fields of pharmaceuticals, agrochemicals, natural products, and functional materials. However, the substrate scope of this reaction is limited owing to the intrinsic difficulty in facilitating multiple catalytic cycles involving several aryllithium species. In this concept paper, recent advances in halogen dance catalysis that have expanded the substrate scope of this reaction are highlighted. [ABSTRACT FROM AUTHOR]

This paper investigates the esterase activity of minimalist amyloid fibers composed of short seven‐residue peptides, IHIHIHI (IH7) and IHIHIQI (IH7Q), with a particular focus on the role of the sixth residue position within the peptide sequence. Through computational simulations and analyses, we explore the molecular mechanisms underlying catalysis in these amyloid‐based enzymes. Contrary to initial hypotheses, our study reveals that the twist angle of the fiber, and thus the catalytic site's environment, is not notably affected by the sixth residue. Instead, the sixth residue interacts with the p‐nitrophenylacetate (pNPA) substrate, particularly through its −NO2 group, potentially enhancing catalysis. Quantum mechanics/molecular mechanics (QM/MM) simulations of the reaction mechanism suggest that the polarizing effect of glutamine enhances catalytic activity by forming a stabilizing network of hydrogen bonds with pNPA, leading to lower energy barriers and a more exergonic reaction. Our findings provide valuable insights into the intricate interplay between peptide sequence, structural arrangement, and catalytic function in amyloid‐based enzymes, offering potentially valuable information for the design and optimization of biomimetic catalysts. [ABSTRACT FROM AUTHOR]

Converting any desired C−H bond to the intended C−Z bond in a given organic molecule could be the final peak of the C−H functionalization methodology. Among the three types of C−H bonds, the functionalization of the ubiquitous C(sp3)−H bond has gained particular attention, especially in the last two decades. There are different ways to transform C(sp3)−H bonds into desired C−Z bonds. The use of chlorine radicals is one of these methods with a promising future. The literature review shows that different sources have been used for chlorine, including chloride ions (HCl or chloride salts), coordinated chlorides (transition metal complexes), and organic chlorides (organochlorine compounds). However, HCl and FeCl3 have gained the most attention among these sources. There are three major ways to convert chlorine from these sources to chlorine radicals: 1) oxidation of hydrogen chloride or chloride salts, 2) photolysis of metal chloride, and 3) transition metal insertion into C−Cl bonds. This review summarizes published research papers on the use of chlorine radicals for C(sp3)−H bonds functionalization. Therefore, chlorination reactions of C(sp3)−H bonds and reactions in which chlorine radicals do not play a direct role in C(sp3)−H bond cleavage are not within the scope of this review. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs), newly developed materials, exhibit considerable promise in the field of catalysis. COFs exhibit captivating catalytic characteristics, including thermal and chemical stability, customizable porosities, and the ability to place active sites flexibly with tunable functions. To establish a connection between structure and activity, this paper provides a thorough justification of the planned creation of covalent organic frameworks for photocatalysis, encompassing H2 production, carbon dioxide reduction, pollutants reduction and transformation of organic substances. We have investigated the catalytic sites that are active within covalent organic frameworks, encompassing the metals, molecular catalysts, and catalyst with single atom (SACs); the reactive skeleton/linkages; and the reactive pendant groups. This exploration aims to establish the benefits of using COF‐based catalysts compared to traditional catalysts. Despite the new advantages, numerous difficulties have also been noted with regard to the future. The objective of this review is to make it easier to design COF‐based composite materials for practical uses. [ABSTRACT FROM AUTHOR]

Glaser‐coupled synthesized 1,3‐diyne can participate in the generation of conjugated polymers and is now widely used in organic and polymer synthesis. Currently, the catalyst in coupling are mostly based on the complexation of noble metals with complex organic ligands, which inevitably increases the research cost and storage difficulty. However, polyoxometalates (POMs), with acidic and redox properties, can be used as an excellent inorganic ligands with low cost and easy storage. In this work, we have synthesized copper catalyst 1, (NH4)4[CuMo6O18(OH)6] with polyoxometalates as inorganic ligands in a facile way and applied them in the coupling of alkynes to obtain (non)symmetrical conjugated 1,3‐diynes in high yields without bases, finally proposing a reasonable reaction path. In addition, the catalyst showed good tolerance to a variety of different groups, further demonstrating its excellent catalytic activity. It is worth mentioning that the catalyst maintained its good structure and activity after six cycles, demonstrating its promising potential for industrial applications. Thus, this paper provides a new strategy for the preparation of (un)symmetrical diynes using polyoxometalates of Cu as catalyst, and also demonstrates the potential of multi‐acid catalyst for organocatalytic applications. [ABSTRACT FROM AUTHOR]

The artificial microenvironments inside coordination cages have gained significant attention for performing enzyme‐like catalytic reactions by facilitating the formation of labile and complex molecules through a "ship‐in‐a‐bottle" approach. Despite many fascinating examples, this approach remains scarcely explored in the context of synthesizing metallic clusters such as polyoxometalates (POMs). The development of innovative approaches to control and influence the speciation of POMs in aqueous solutions would greatly advance their applicability and could ultimately lead to the formation of elusive clusters that cannot be synthesized by using traditional methods. In this study, we employ host–guest stabilization within a coordination cage to enable a novel cavity‐directed synthesis of labile POMs in aqueous solutions under mild conditions. The elusive Lindqvist [M6O19]2− (M=Mo or W) POMs were successfully synthesized at room temperature via the condensation of molybdate or tungstate building blocks within the confined cavity of a robust and water‐soluble Pt6L4(NO3)12 coordination cage. Importantly, the encapsulation of these POMs enhances their stability in water, rendering them efficient catalysts for environmentally friendly and selective sulfoxidation reactions using H2O2 as a green oxidant in a pure aqueous medium. The approach developed in this paper offers a means to synthesize and stabilize the otherwise unstable metal‐oxo clusters in water, which can broaden the scope of their applications. [ABSTRACT FROM AUTHOR]

In this paper, Pd‐catalyzed [4+2] decarboxylative cycloaddition of 4‐vinylbenzodioxinones with barbiturate‐derived alkenes has been developed, leading to various spirobarbiturate−chromane derivatives in high yields with excellent diastereo‐ and enantioselectivities. The scale‐up reaction and further derivation of the product were demonstrated. A plausible reaction mechanism was also proposed. [ABSTRACT FROM AUTHOR]

The use of hierarchically structured materials as catalysts has been finding increasing application in the past years. For these catalytic systems, not only the nano‐scale matters: a high degree of order across multiple length scales, along with its control and analytical assessment, is of paramount importance to obtain innovative properties that can find application in catalysis. Most reviews dealing with hierarchically structured materials are concerned with the "bottom‐up" transfer of structural information along the different length scales, with special emphasis on the transmission of chirality. Due to their mesoscale size together with their complex behaviour, these systems are often susceptible to feel the effects of macroscopic forces, that can exert a "top‐down" control of their catalytic properties, so that an external stimulus, acting at the level of the supramolecular architecture of the catalyst, can ultimately determine the outcome of the catalyzed reaction at the molecular level. We review in this paper some recent reports that deal with the experimental implementation of this concept, either by using a mechanical force in a full range direct transmission to the reaction coordinate, or by means of a stepwise relay transmission from the macroscopic level (purely supramolecular chirality) to the nanoscopic one. We focus in this review on these multi‐length scale communication control effects, identifying the different mechanisms that are affecting the catalytic activity. [ABSTRACT FROM AUTHOR]

This paper presents a Mn(I)‐catalysed methodology for the enantioselective hydrophosphination of terminal alkenyl aza‐heteroarenes. The catalyst operates through H−P bond activation, enabling successful hydrophosphination of a diverse range of alkenyl‐heteroarenes with high enantioselectivity. The presented protocol addresses the inherently low reactivity and the commonly encountered suboptimal enantioselectivities of these challenging substrates. As an important application we show that this method facilitates the synthesis of a non‐symmetric tridentate P,N,P‐containing ligand like structure in just two synthetic steps using a single catalytic system. [ABSTRACT FROM AUTHOR]

In this paper, we report BF3 ⋅ OEt2 as a catalyst to shuttle equivalents of HF from a fluoroalkane to an alkyne. Reactions of terminal and internal aliphatic alkynes led to formation of difluoroalkane products, while diarylalkynes can be selectively converted into fluoroalkenes. The method tolerates numerous sensitive functional groups including halogen, protected amine, ester and thiophene substituents. Mechanistic studies (DFT, probe experiments) suggest the catalyst is involved in both the defluorination and fluorination steps, with BF3 acting as a Lewis acid and OEt2 a weak Lewis base that mediates proton transfer. In certain cases, the interconversion of fluoroalkene and difluoroalkane products was found to be reversible. The new catalytic system was applied to demonstrate proof‐of‐concept recycling of poly(vinylidene difluoride). [ABSTRACT FROM AUTHOR]

Non‐thermal plasma (NTP) catalysis, mirroring the trend towards non‐conventional electron‐mediated molecular activation, unfolds novel routes for chemical reactions. Operating at ambient pressure, lower temperatures, and energized by electricity that can powered by renewable sources, NTP offers a cost‐effective and efficient means of sustainable fuel production. This approach has the potential to revolutionize the oil and gas industry, meeting current energy demands while circumventing the challenges posed by conventional thermal catalysis processes, thereby enhancing environmental sustainability and energy security. Through an exploration of the synergistic effects between plasma, catalysis, and hydrocarbon molecules, this concept paper emphasizes the significant advancements made in in‐liquid plasma catalysis strategies for fuel production from heavy oil upgrading. We also provide insights into the heterogeneous catalyst design and the role of plasma gas as an additional catalyst for achieving efficient and sustainable energy solutions. The prospects of in‐liquid plasma catalysis, emphasizing its transformative role in shaping the energy future, are also discussed. [ABSTRACT FROM AUTHOR]

Lignin, an inherently heterogeneous arylpropanoid polymer, presents a unique resource for the sustainable manufacture of aromatic chemicals and fuels. Recently, numerous catalytic strategies for lignin valorization have been explored. Polyoxometalates (POMs), with their distinctive structures enabling control of redox processes in lignin conversion, have been of particular interest. However, a comprehensive assessment of this emerging field of study is currently missing. This paper aims to fill this gap with a detailed review of the use of POMs for catalytic lignin conversion into value‐added compounds. This review delves into various catalytic lignin conversion techniques, including thermal catalysis, electrocatalysis, and tandem processes for lignin separation, depolymerization, and upgrading. Moreover, we highlight innovative investigations utilizing polyoxometalate‐ionic liquids (POM‐ILs), POM‐deep eutectic solvents (POM‐DESs), and solidification or immobilization techniques for POMs as lignin valorization catalysts. Lastly, we discuss the future prospects and challenges in the domain of POM catalytic lignin conversion. [ABSTRACT FROM AUTHOR]

Biohybrid catalysts that operate in aqueous media are intriguing for systems chemistry. In this paper, we investigate whether control over the self‐assembly of biohybrid catalysts can tune their properties. As a model, we use the catalytic activity of functional hybrid molecules consisting of a catalytic H‐dPro‐Pro‐Glu tripeptide, derivatized with fatty acid and nucleobase moieties. This combination of simple biological components merged the catalytic properties of the peptide with the self‐assembly of the lipid, and the structural ordering of the nucleobases. The biomolecule hybrids self‐assemble in aqueous media into fibrillar assemblies and catalyze the reaction between butanal and nitrostyrene. The interactions between the nucleobases enhanced the order of the supramolecular structures and affected their catalytic activity and stereoselectivity. The results point to the significant control and ordering that nucleobases can provide in the self‐assembly of biologically inspired supramolecular catalysts. [ABSTRACT FROM AUTHOR]

A series of new pyrazolate and mixed pyrazolate/pyrazole magnesium complexes is described and their reactivity toward carbon dioxide is examined. The dimeric complex [Mg(pztBu,tBu)2]2 inserts CO2 instantly and quantitatively forming the tetrameric complex [Mg(CO2·pztBu,tBu)2]4 and monomeric donor‐stabilized [Mg(CO2·pztBu,tBu)2(thf)2]. Complexes of the type [Mgx(pzR,R)2x(HpzR,R)y]n (R = iPr, tBu) engage in similar insertion reactions involving dissociation of the carbamic acid HOOCpzR,R. Even solid polymeric derivatives [Mg(pzR,R)2]n (R = Me, H) react instantaneously and exhaustively with CO2, the resulting [Mg(CO2·pz)2]m featuring a CO2 capacity of 35.7 wt% (8.2 mmol g−1). All described magnesium pyrazolates display completely reversible CO2 uptake in solution and in the solid state, respectively, as monitored via VT 1H NMR and in situ FTIR spectroscopy as well as thermogravimetric analysis. Fluorinated [Mg2(pzCF3,CF3)4(thf)3] does not yield any isolable CO2 insertion product but exhibits the highest activity in the catalytic transformation of epoxides and CO2 to cyclic carbonates. [ABSTRACT FROM AUTHOR]

The world is facing grand challenges in energy security, environmental pollution, and sustainable use (and re‐use) of resources. Electrochemical processes, incorporating electrosynthesis, electrochemical catalysis, and electrochemical energy storage devices, provide pathways to address these challenges via green chemistry. However, the applicability of electrochemical processes for these systems is limited by the required energy input, the "electrons" in electrochemistry. Electrocatalysis as a subset of electrochemistry is set to underpin many of the United Nations Sustainable Development Goals, including "Affordable and Clean Energy" through the production of future fuels and abatement of carbon emissions; "Responsible Consumption and Production" through recycling and degradation of waste; and "Climate Action" through CO2 (and other greenhouse gas) remediation. The rise of green photovoltaic power has lowered the carbon cost of these electrons, making electrocatalysis an even more viable, green(er), chemical conversion pathway. This perspective highlights the need for comprehensive understanding of catalyst structure via in situ and operando analysis to complement device design considerations. The challenges faced by the field of electrocatalysis in data reporting, elimination of electrochemical artifacts, catalyst stability, and scaling to industrial relevance, along with opportunities, emerging tools, are discussed with a view to achieve the maximum 'potential' of electrocatalysis. [ABSTRACT FROM AUTHOR]

Allostery is an important property of biological macromolecules which regulates diverse biological functions such as catalysis, signal transduction, transport, and molecular recognition. However, the concept was expressed using two different definitions by J. Monod and, over time, more have been added by different authors, making it fuzzy. Here, we reviewed the different meanings of allostery in the current literature and found that it has been used to indicate that the function of a protein is regulated by heterotropic ligands, and/or that the binding of ligands and substrates presents homotropic positive or negative cooperativity, whatever the hypothesized or demonstrated reaction mechanism might be. Thus, proteins defined to be allosteric include not only those that obey the two‐state concerted model, but also those that obey different reaction mechanisms such as ligand‐induced fit, possibly coupled to sequential structure changes, and ligand‐linked dissociation‐association. Since each reaction mechanism requires its own mathematical description and is defined by it, there are many possible 'allosteries'. This lack of clarity is made even fuzzier by the fact that the reaction mechanism is often assigned imprecisely and/or implicitly in the absence of the necessary experimental evidence. In this review, we examine a list of proteins that have been defined to be allosteric and attempt to assign a reaction mechanism to as many as possible. [ABSTRACT FROM AUTHOR]

Metal borides have received a lot of attention recently as a potentially useful material for a wide range of applications. In particular, molybdenum‐based borides and MBenes are of great significance, due to their remarkable properties like good electronic conductivity, considerable stability, high surface area, and environmental harmlessness. Therefore, in this article, the progress made in molybdenum‐based borides and MBenes in recent years is reviewed. The first step in understanding these materials is to begin with an overview of their structural and electronic properties. Then synthetic technologies for the production of molybdenum borides, such as high‐temperature/pressure methods, physical vapor deposition (PVD), chemical vapor deposition (CVD), element reaction route, molten salt‐assisted, and selective etching methods are surveyed. Then, the critical performance of these materials in numerous applications like energy storage, catalysis, biosensors, biomedical devices, surface‐enhanced Raman spectroscopy (SERS), and tribology and lubrication are summarized. The review concludes with an analysis of the current progress of these materials and provides perspectives for future research. Overall, this review will offer an insightful reference for the understanding molybdenum‐based borides and their development in the future. [ABSTRACT FROM AUTHOR]

In recent years, there has been a surge in annual plastic production, which has contributed to growing environmental challenges, particularly in the form of microplastics. Effective management of plastic and microplastic waste has become a critical concern, necessitating innovative strategies to address its impact on ecosystems and human health. In this context, catalytic degradation of microplastics emerges as a pivotal approach that holds significant promise for mitigating the persistent effects of plastic pollution. In this article, we critically explored the current state of catalytic degradation of microplastics and discussed the definition of degradation, characterization methods for degradation products, and the criteria for standard sample preparation. Moreover, the significance and effectiveness of various catalytic entities, including enzymes, transition metal ions (for the Fenton reaction), nanozymes, and microorganisms are summarized. Finally, a few key issues and future perspectives regarding the catalytic degradation of microplastics are proposed. [ABSTRACT FROM AUTHOR]

Homogenous catalysis is an essential tool within the commercial manufacture of bulk and fine chemicals. Within this, phosphine ligands, such as tricyclohexylphosphine, otherwise known as CYTOP® 366, are a crucial component. When designing a pathway to your ligand of choice, some key considerations include safety, yield and quality, but at commercial volumes we must also balance cost and consider the technologies readily available. Herein, we report the synthetic route that was chosen to manufacture tricyclohexylphosphine at commercial scale. We also consider, with the use of computational calculations, why traditional hydrophosphination methods failed, where the selected pathway succeeded. [ABSTRACT FROM AUTHOR]

In an article published in Advanced Functional Materials, researchers Amit Kumar, In Su Lee, and their colleagues discuss their findings on electrochemical ultrathin metal-atomic layer deposition for silica microenvironment-assisted Cu-based catalysis. They demonstrate the formation of a sandwiched structure consisting of a 2D-Cu nanolayer grown electrochemically on a carbon paper inside a porous bilayer silica template. This structure, with its extended and intimate 2D-2D silica-Cu interface, acts as a catalyst for the selective hydrogenation of alkynes to alkenes. [Extracted from the article]

Electrochemical ammonia oxidation reaction (eAOR) regains interest due to ammonia being an interesting alternative to hydrogen for fuel cell technologies. In the present review, we first discuss some of the most important findings on eAOR with solid catalysts, including mechanistic and feasibility aspects for practical implementation. We then examine the reports on molecular catalysis of eAOR that have recently emerged. We finally discuss immobilization strategies of these molecular catalysts, and discuss intrinsic advantages of those strategies, so as to guide the design of efficient catalytic systems able to compete with heterogeneous, solid catalysts. [ABSTRACT FROM AUTHOR]

A family of transition metal complexes of meso‐aryl‐2‐aza‐21‐carbaporphyrin (N‐confused porphyrin, NCP) derivatives acting as ortho‐metallating ligands for ruthenium(II), rhodium(III), and iridium(III) is synthesized and characterized by XRD, spectroscopic, and electrochemical methods. The chirality of these systems is shown by the separation of the enantiomers and analyzed by circular dichroism and DFT. A preliminary catalytic study indicates the activity of the iridium(III) ortho‐metallated complexes in the N‐heterocyclization of primary amines with diols. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of complicated multiphase conversions and the severe shuttling effect of lithium polysulfides (LiPSs) significantly hinder the applications of Li‐S battery, which is one of the most promising candidates for the next‐generation energy storage system. Herein, a bifunctional electrocatalyst, indium phthalocyanine self‐assembled with carbon nanotubes (InPc@CNT) composite material, is proposed to promote the conversion kinetics of both reduction and oxidation processes, demonstrating a bidirectional catalytic effect on both nucleation and dissolution of Li2S species. The theoretical calculation shows that the unique electronic configuration of InPc@CNT is conducive to trapping soluble polysulfides in the reduction process, as well as the modulation of electron transfer dynamics also endows the dissolution of Li2S in the oxidation reaction, which will accelerate the effectiveness of catalytic conversion and facilitate sulfur utilization. Moreover, the InPc@CNT modified separator displays lower overpotential for polysulfide transformation, alleviating polarization of electrode during cycling. The integrated spectroscopy analysis, HRTEM, and electrochemical study reveal that the InPc@CNT acts as an efficient multifunctional catalytic center to satisfy the requirements of accelerating charging and discharging processes. Therefore, the Li–S battery with InPc@CNT‐modified separator obtains a discharge‐specific capacity of 1415 mAh g−1 at a high rate of 0.5 C. Additionally, the 2 Ah Li–S pouch cells deliver 315 Wh kg−1 and achieved 80% capacity retention after 50 cycles at 0.1 C with a high sulfur loading of 10 mg cm−2. Our study provides a practical method to introduce bifunctional electrocatalysts for boosting the electrochemical properties of Li–S batteries. [ABSTRACT FROM AUTHOR]

Inhospitable, inaccessible, and extremely remote alike the famed pole of inaccessibility, aka Point Nemo, the isolated locations in deserts, at sea, or in outer space are difficult for humans to settle, let alone to thrive in. Yet, they present a unique set of opportunities for science, economy, and geopolitics that are difficult to ignore. One of the critical challenges for settlers is the stable supply of energy both to sustain a reasonable quality of life, as well as to take advantage of the local opportunities presented by the remote environment, e.g., abundance of a particular resource. The possible solutions to this challenge are heavily constrained by the difficulty and prohibitive cost of transportation to and from such a habitat (e.g., a lunar or Martian base). In this essay, the advantages and possible challenges of integrating Fischer–Tropsch, artificial photosynthesis, and plasma catalysis into a robust, scalable, and efficient self‐contained system for energy harvesting, storage, and utilization are explored. [ABSTRACT FROM AUTHOR]