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Inadequate treatment of industrial waste causes the contamination of rivers and seas, impacting human health and aquatic biodiversity. Among the pollutants are industrial dyes, such as methylene blue (MB), which is toxic in high doses and prevents solar radiation from penetrating the water’s surface. To reduce water pollution, the organic dyes could be degraded, generating less harmful and colorless substances. The use of nanoparticles as catalysts has been gaining attention since they have excellent catalytic activity due to their high surface-to-volume ratio. Thus, this work aims to study the use of silver nanoparticles (AgNPs) to degrade MB. AgNPs were prepared in water using the chemical reduction strategy and four different organic stabilizers: sodium citrate, ascorbic acid, polyvinylpyrrolidone, and poly(vinyl alcohol). The MB degradation in the presence of the AgNPs was monitored by UV-Vis absorption spectroscopy. The results showed the formation of AgNPs with a spherical shape for all the stabilizers used. All the AgNPs prepared were efficient in the degradation of MB, having degraded more than 90%. However, the AgNPs stabilized with sodium citrate and polyvinylpyrrolidone presented the best catalytic performance. Nevertheless, the four AgNPs prepared are potential catalysts for the degradation of organic dyes of wastewater.

Abstract Hydrogen is the most preferred choice as an energy source to replace the nonrenewable energy resources such as fossil fuels due to its beneficial features of abundance, ecofriendly, and outstanding gravimetric energy density. Splitting water through a proton exchange membrane (PEM) electrolyzer is a well‐known method of hydrogen production. But the major impediment is the sluggish kinetics of oxygen evolution reaction (OER). Currently, scientists are struggling to build out an acid‐stable electrocatalyst for OER with low overpotential and excellent stability. In this review, the reaction mechanism and characterization parameters of OER are introduced, and then the improvement method of metal nanocatalysts (noble metal catalysts and noble metal‐free catalysts) in acidic media is discussed. Particularly, the application of single‐atom catalysts in acidic OER is summarized, which is current researching focus. At the same time, we also briefly introduced the cluster phenomenon, which is easy to occur in the preparation of single‐atom catalysts. More importantly, we summarized the in situ characterization methods such as in situ X‐ray absorption spectroscopy, in situ X‐ray photoelectron spectroscopy, and so forth, which are conducive to further understanding of OER reaction intermediates and active sites. Finally, we put forward some opinions on the development of acidic OER.

Hybrid nano‐biomaterials are exploited in the design and performance of chemo‐enzymatic cascades. In this study, lipase is immobilized from Candida antarctica fraction B (CALB) and gold nanoparticles (Au NPs) on magnetic particles coated with silica (MNP@SiO2) to stepwise hydrolyze and reduce p‐nitrophenyl esters in tandem reaction. The assembly of the two catalysts at the interface of the MNP@SiO2 particles and the temporal control of the reaction turns out to be the most determinant parameters for the cascade kinetics. When both CALB and Au NPs are co‐immobilized at the MNP@SiO2 particle, the tandem reactions take place significantly faster than when both catalysts are physically segregated by their immobilization on different MNP@SiO2 particles. Herein, it is demonstrated that the co‐immobilization of biocatalysts and nanocatalysts in solid materials creates hybrid interfaces that accelerated chemo‐enzymatic tandem reactions. [ABSTRACT FROM AUTHOR]

Entanglement of spatial and/or temporal scales proposes great challenges to unravel mechanisms of complex chemical systems for their rational design. Multiscale modeling and calculations combining theoretical methods and algorithms at different scales provide powerful tools to address such problems. It has been conventionally known that energetics such as the reaction barrier plays an essential role in complex systems involving chemical reactions, in this review, we focus on recent progress of mechanisms beyond energetics revealed by multiscale kinetic modeling to emphasize the variety of underlying mechanism for such systems, and highlights the importance of kinetics in multiscale modeling and calculations for practical applications. Several interesting mechanisms as well as the corresponding concepts of multiscale kinetic modeling are described in detail, ranging from effects of geometry, micro‐orientation, or reactant flux on 2D material epitaxial growth, to diffusion, directional mass transfer, or confinement enhanced electrocatalysis on nanocatalysts. This article is categorized under:Theoretical and Physical Chemistry > Reaction Dynamics and Kinetics [ABSTRACT FROM AUTHOR]

We performed the Ru nanoparticles encapsulation using silica-coated carbon-cobalt nanostructure (with and without amine functionality). The physicochemical properties of the above structures were evaluated using the following analytical techniques such as XPS, EDX, XRD, HR-TEM, and ICP-AES. The analytical data received from the above analysis were found in good correlation to each other and confirm the uniform distribution of ruthenium nanoparticles over the surface of the silica–carbon coated magnetic cobalt system. The uniform Ru dispersion confirms the high catalytic activity during CO2 hydrogenation reaction to formic acid. We also studied the effect of water and correlated the same with the quantity of formic acid. Easy catalyst preparation, hassle-free catalyst isolation under an applied magnetic field, and good catalyst recycling is the major outcome of this proposed work. The effect of the ionic liquid solvent system was also noticed in terms of high reaction rate, good catalyst stability, and nine times catalyst recycling. [ABSTRACT FROM AUTHOR]

3-Alkenylindoles are biologically and medicinally very important compounds, and their syntheses have received considerable attention. Herein, we report the synthesis of 3-alkenylindoles via a regioselective alkenylation of indoles, catalysed by a ruthenium nanocatalyst (RuNC). The reaction tolerates several electron-withdrawing and electron-donating groups on the indole moiety. Additionally, a “robustness screen” has also been employed to demonstrate the tolerance of several functional groups relevant to medicinal chemistry. With respect to the Ru nanocatalyst, it has been demonstrated that it is recoverable and recyclable up to four cycles. Also, the catalyst acts through a heterogeneous mechanism, which has been proven by various techniques, such as ICPMS and three-phase tests. The nature of the Ru nanocatalyst surface has also been thoroughly examined by various techniques, and it has been found that the oxides on the surface are responsible for the high catalytic efficiency of the Ru nanocatalyst.

Abstract The catalytic activity of snowman‐like and core‐shell Fe3O4/Au nanoparticles (NPs), obtained through a “wet chemistry” approach which directly restitutes nanocatalysts stable and highly active in the reaction medium, was tested towards N‐alkylation reactions. The nanocatalysts were tested for the synthesis of secondary amines. The core‐shell NPs, thanks to the surface properties, homogeneous dispersion and intimate connection with reagents in the catalyst medium, exhibited an excellent catalytic activity (e. g. >99 % yield and conversion of aniline in very short time and mild conditions). Owing to the magnetic part, the nanoparticles can be easily separated and reused, showing an almost stable activity after 10 cycles.

The development of ingenious technologies for the purification of wastewater containing highly toxic organic compounds is of high importance in the current research. The application of noble metal nanocatalysts in the presence of sodium borohydride (NaBH4) for the removal of these toxic compounds through chemical reduction method have become an accepted approach in the recent years. The present work reports on the development of a convenient approach to fabricate free standing, robust, and flexible reduced graphene oxide ‐ silver/polyvinyl alcohol (rGO−Ag/PVA) nanocomposite film. The morphological and structural characterizations of the as developed film have been carried out using SEM, TEM, EDAX, Raman, BET, and TGA. The performance of as developed rGO−Ag/PVA nanocomposite film is tested as heterogeneous catalyst in the reduction reaction of 4‐Nitrophenol and reduction of Methyl Orange dye. The nanocomposite film‐based catalyst exhibited excellent catalytic performances as well as excellent stability in the reduction of toxic organic compounds in wastewater. [ABSTRACT FROM AUTHOR]

The present paper reports the preparation of zirconium-based metal–organic framework (Zr-MOF) nanocomposites, which were fabricated on the surface of a reduced graphene oxide (rGO) sheet via an in situ method. The Zr-MOF/rGO-nanocatalyst is successfully synthesized and tested for 2,3-dihydroquinazolin-4-(1H)-one derivative with isolated yields (89–97%) within 30 min. We have also synthesized a total of 14 aromatic derivatives of 2,3-dihydroquinazolin-4-(1H)-one compound and evaluated the possible binding of these compounds to the calf-thymus DNA (CT-DNA). Furthermore, binding with CT-DNA is examined by the fluorescence spectroscopic technique and molecular docking studies. Fluorescence studies show G12, G13, and G14 compounds and give the best results amongst all synthesized 2,3-dihydroquinazolin-4-(1H)-one derivatives. Allosteric inhibition of CT-DNA is performed and evaluated by molecular docking studies based on minimum binding energy, which corresponds to the fluorescence results. These comparative results proved G12, G13, and G14 compounds bind more effectively as compared to 3,8-diamino-5-ethyl-6-phenylphenanthridinium bromide. The characterization of the Zr-MOF/rGO-nanocatalyst is elucidated through Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy, thermogravimetric analysis, field emission scanning electron microscopy, high-resolution transmission electron microscopy Raman spectrum, inductively coupled plasma optical emission spectroscopy, and nuclear magnetic resonance spectroscopy. The present nanocatalyst is readily recycled, reused five times, and found to be stable, with stability confirmed through FTIR spectroscopy and PXRD. [ABSTRACT FROM AUTHOR]

Single atoms are nowadays considered new catalysts offering a lot of advantages such as reduced cost and use of noble metals. Here, we report the catalytic activity towards N‐alkylation reactions of single atoms (SACs) of iridium doped polypyrrole (Ir−PPy nanoparticles). The new nanocatalyst exhibits excellent behavior due to the combination of highly active SACs catalyst and the organic conductive support providing strong binding of single atoms and thus improved reusability and easiness to handle. In the presence of a low amount of Ir and of a suitable base, excellent activity (yield >99 %) and selectivity (>99 %) were obtained. In the optimized Ir condition (3 wt.% of Ir) an aniline conversion of about 99 %, with excellent selectivity, just after 600 min, was obtained. Recyclability tests show that the catalyst can be successfully recycled six times without significant catalyst activity loss. [ABSTRACT FROM AUTHOR]

Nanocatalytic-based wound therapeutics present a promising strategy for generating reactive oxygen species (ROS) to antipathogen to promote wound healing. However, the full clinical potential of these nanocatalysts is limited by their low reactivity, limited targeting ability, and poor biodegradability in the wound microenvironment. Herein, a bio-organic nanozyme is developed by encapsulating a FeZn-based bimetallic organic framework (MOF) (MIL-88B-Fe/Zn) in platelet membranes (PM@MIL-88B-Fe/Zn) for antimicrobial activity during wound healing. The introduction of Zn in MIL-88B-Fe/Zn modulates the electronic structure of Fe thus accelerating the catalytic kinetics of its peroxidase-like activity to catalytically generate powerful ROS. The platelet membrane coating of MOF innovatively enhanced the interaction between nanoparticles and the biological environment, further developing bacterial-targeted therapy with excellent antibacterial activity against both gram-positive and gram-negative bacteria. Furthermore, this nanozyme markedly suppressed the levels of inflammatory cytokines and promoted angiogenesis in vivo to effectively treat skin surface wounds and accelerate wound healing. PM@MIL-88B-Fe/Zn exhibited superior biodegradability, favourable metabolism and non-toxic accumulation, eliminating concerns regarding side effects from long-term exposure. The high catalytic reactivity, excellent targeting features, and biodegradability of these nanoenzymes developed in this study provide useful insights into the design and synthesis of nanocatalysts/nanozymes for practical biomedical applications., (© 2023 Wiley‐VCH GmbH.)

Removing one key barrier to the industrial uptake of green chemistry and nanocatalysis in the fine and specialty chemical industry requires to fill an ongoing “talent shortage” via expanded chemistry education. In this study we show how the use of hybrid sol-gel catalysts to synthesize fine chemicals and active pharmaceutical ingredients in flow chemistry reactors illustrates new ideas to reshape chemistry education based on recent research outcomes, visualization and digital tools. Aiming to expand the knowledge base, skills and competencies that comprise the aforementioned new professional talent in catalysis and green chemistry currently in high demand, we identify several lessons learned from the industrial and academic utilization of these materials.

Copper nanostructures are promising catalysts for the electrochemical reduction of CO2 because of their unique ability to produce a large proportion of multi‐carbon products. Despite great progress, the selectivity and stability of such catalysts still need to be substantially improved. Here, we demonstrate that controlling the surface oxidation of Cu nanowires (CuNWs) can greatly improve their C2+ selectivity and stability. Specifically, we achieve a faradaic efficiency as high as 57.7 and 52.0 % for ethylene when the CuNWs are oxidized by the O2 from air and aqueous H2O2, respectively, and both of them show hydrogen selectivity below 12 %. The high yields of C2+ products can be mainly attributed to the increase in surface roughness and the generation of defects and cavities during the electrochemical reduction of the oxide layer. Our results also indicate that the formation of a relatively thick, smooth oxide sheath can improve the catalytic stability by mitigating the fragmentation issue. [ABSTRACT FROM AUTHOR]

Deep oxidation/dehydrogenation are longstanding problems for decades in catalytic oxidative dehydrogenation (ODH) of cyclohexane and other alkanes. Here we show a metal‐free catalyst of nanodiamonds (NDs) with unique sp3@sp2 hybrid structure that catalyzes COx‐resistant cyclohexane ODH with remarkable reactivity towards cyclohexene production. The selectivity of cyclohexene can reach as high as 67 % with significantly suppressed COx emission (<5 %), which is on top of the highest reported values among other metal(oxide)/metal‐free catalysts. Structural evolution of sp3@sp2 NDs under annealing treatments and their specific surface functional groups are systematically studied using TEM, XPS, Raman and TPD. By comparing with carbon nanotubes (CNTs), we found that the carbonyl groups stabilized on strained sp3@sp2 core‐shell NDs enhanced the cyclohexene selectivity via preferential cleavage of C−H over C−C bond. Kinetic studies further revealed the underlying reaction pathways that cyclohexane is rapidly dehydrogenated to cyclohexene which subsequently transforms into benzene (fast) and COx (slow). Deep oxidation of both cyclic hydrocarbons is largely suppressed due to the low density of electrophilic functional groups on strongly curved graphitic surface of sp3@sp2 NDs. [ABSTRACT FROM AUTHOR]

Spiroannulated hybrid molecules with privileged substructures have been synthesized by an efficient and sustainable synthetic protocol involving isocyanide‐based four component reaction of benzene‐1,2‐diamine, 2‐hydroxynaphthalene‐1,4‐dione, cyclic ketones and isocyanides catalyzed by recyclable and reusable nanostructured TiO2 with Erbium(Er) doping as heterogeneous catalyst. The synthetic protocol with special features, that is, atom and step economy, operational simplicity, synthetic efficiency and superior catalytic activity with sustainability and its recyclability and reusability provided structurally diverse hybrid molecules with unique combination of privileged substructures. The present synthetic protocol will contribute significantly to drug discovery research in view of its synthetic efficiency to synthesize drug‐like molecules with structural complexity. The catalyst was successfully synthesized and characterized by X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FT‐IR), energy‐dispersive X‐ray spectroscopy (EDX), and transmission electron microscopy (TEM). [ABSTRACT FROM AUTHOR]

At the industrial level, Ag catalysts in the form of silver crystals held by a silver gauze are largely used for formaldehyde production and ethylene epoxidation. These self-supported structures undergo surface reconstructions and morphological changes upon exposure to moderately high temperatures (473–900 K) and oxidising atmospheres. These phenomena have been studied and well understood on single crystal surfaces and polycrystalline foils: different oxygen surface and sub-surface species have been identified and reconstruction processes explained. To verify the scalability of the surface science results and ultimately understand these phenomena on catalysts at the industrial scale, further studies on more complex samples are needed. Attempts to close this "materials gap" have been carried out in this present study where experiments have been performed on model single catalytic nanoparticles, i.e. the apexes of field emitter tips, using both field emission (FE) and field ion (FI) microscopies. Pure Ag samples are exposed to a pressure of 3 × 10–5 mbar of O2 at temperatures up to 700 K. These conditions reflect those used on the industrial scale. Important surface/morphological reconstructions are observed both in FE and FI modes. For comparison, experiments have been repeated on Au-8.8%at. Ag field emitter tips, representative samples for Au–Ag catalytic nanofoams, using to 3 × 10–5 mbar of NO2 at temperatures up to 450 K. Similar behaviour are observed and the influence of the oxidising gas is discussed. [ABSTRACT FROM AUTHOR]

The oxygen adsorption and its catalytic reaction with hydrogen on Pt–Rh single crystals were studied at the nanoscale by Field Emission Microscopy (FEM) and Field Ion Microscopy (FIM) techniques at 700 K. Both FEM and FIM use samples prepared as sharp tips, apexes of which mimic a single nanoparticle of catalyst considering their similar size and morphology. Oxygen adsorption on Pt-17.4 at.%Rh samples leads to the formation of subsurface oxygen, which is manifested in the field emission (FE) patterns: for O2 exposure of ~3 Langmuir (L), {113} planes appear bright in the emission pattern, while for higher oxygen doses, i.e. 84 L, the bright regions correspond to the high index planes between the {012} and {011} planes. Formation of subsurface oxygen is probably accompanied by a surface reconstruction of the nanocrystal. The subsurface oxygen can be effectively reacted off by subsequent exposure of the sample to hydrogen gas at 700 K. The hydrogenation reaction was observed as a sudden, eruptive change of the brightness seen on the FE pattern. This reaction resulted in the recovery of the initial field emission pattern characteristic of a clean tip, with {012} facets being the most visible. It was shown that the oxygen accumulation-reduction process is completely reversible. The obtained results indicate that the presence of subsurface species must be considered in the description of reactive processes on Pt–Rh catalysts. [ABSTRACT FROM AUTHOR]

The 1,3‐dipolar cycloadditions of azomethine‐ylides and ‐imines, nitrones, nitrilimines, and azides catalysed by inorganic nanoparticles are described. Emphasis is given to the nanometric catalysts involved, their structure, characterisation, and recyclability and, when remarkable, their preparation. Whenever possible, the improvements with respect to cycloadditions performed with the usual (non‐nano) catalysts are discussed. [ABSTRACT FROM AUTHOR]

An efficient and environmentally sustainable domino protocol has been presented for the synthesis of structurally diverse spiroannulated indolo[3,2‐c]quinolines involving three component sequential reaction of phenylhydrazine, o‐aminoacetophenone and cyclic ketones using nanostructured terbium doped TiO2 as recyclable and reusable heterogeneous catalyst. The nanostructured catalyst was synthesized successfully and characterized by X‐ray Diffraction (XRD), transmission electron microscopy (TEM), EDX and Fourier transform infra‐red spectroscopy (FTIR). The substitution of Ti+4 with Tb+3 and the formation of Ti‐O‐Tb bonds as a result of doping of Terbium with TiO2 NPs increases the catalytic efficiency and facilitates the reaction to provide the products in excellent yields. The present protocol with special features; operational simplicity, atom‐economy, mild reaction conditions, environmental sustainability and high synthetic efficiency with recyclability and reusability of catalyst has been reported for the first time to synthesize spiroannulated indoloquinolines and expecting to provide the library of promising new leads in drug discovery research. [ABSTRACT FROM AUTHOR]

Nanotechnology has produced compelling evidences in the field of catalysis, construction, electronics, energy, food, imaging, medical, packaging, pharmaceutical sectors and in water treatment. Nanoparticles of transition metal origin are enticing in catalytic applications due to their low‐lying empty orbitals for bonding and can offer a distinct ability to expand the coordination sphere. This coupled with ease of synthesis, recyclability and occurrence in abundance staples them as unique industrial materials. Transition metals such as Gold, Palladium, Silver, Copper, Iron, Ruthenium, Rhodium and hetero‐bimetallic versions have been in demand for various organic transformations. The sharp rise in number of literature reports justifies the stand in catalytic property. A unique ability to form Covalent and/or Van der Waals interactions with solid supports and activate the substrates through close functional group interactions renders them as effective entities in organic transformations. In this review, we present the new developments in this niche in the past five years with a retreat on the mechanistic aspects along with parameters involved in nanoparticle characterizations through advances in spectroscopy. [ABSTRACT FROM AUTHOR]

In this work, a novel polyvinyl alcohol sponge supported Ni catalyst was obtained by the modified im-pregnation and self-assembly method. The Ni/PVA catalyst exhibits excellent catalytic performance in the catalytic reduction of p-nitrophenol. When the loading amount of Ni nanoparticles (NiNPs) was 500 rag and the injection speed was 3 mL/min, the conversion rate of 4-NP was close to 100%. It also maintained the conversion of 95% after 6 recycling time because the PVA sponge could reduce the chances of leaching and aggregation for NiNPs. The unique structure of PVA not only effectively inhibits the agglomeration of NiNPs, but also ensures the stability of the Ni/PVA catalyst. Ni/PVA catalyst, which has the characteristics of high catalytic efficiency, reusability and low cost, has great development potential in the field of water treatment. [ABSTRACT FROM AUTHOR]

In this study, we synthesized a robust and sustainable Pd/SiO2 nanospheres catalyst. Further, its catalytic activity was demonstrated for the direct reductive coupling of nitroarenes under mild conditions. While the reaction with Pd nanoparticles on other supporting materials such as modified carbon materials and TiO2, under similar conditions, resulted formation of amines exclusively. Therefore, it was confirmed that the SiO2 was found to be the best supporting material towards the selective reductive coupling of nitroarenes. Also, the catalyst could be recycled up to five cycles with a marginal loss of product yield (< 2% yield). [ABSTRACT FROM AUTHOR]

The nano-grade titanium dioxide set on multi-walled carbon nanotubes (nano-TIO2@-MWCNTs) composite has been first tested as a potential catalyst in the aerobic oxidation of isopropylbenzene. It has been determined by changing active oxygen content that nano-TIO2@-MWCNTs begins to actively decompose cumene hydroperoxide at temperatures above 100 degrees.Kinetic correlations and curves of oxygen uptake for cumene liquid-phase initiated (AIBN)oxidation in the presence of nano-TIO2@MWCNTs are presented. Nano-TIO2@MWCNTs was found to be efficient catalyst of the profound cumene liquid-phase aerobic oxidation at moderate temperatures, affording a number of valuable products. Nano-TIO2@MWCNTs may be recommended as active catalyst for aerobic oxidation of alkyl aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

A simple, solvent-free, faster and mechanochemical approach for the N-tert-butoxycarbonylation of amines catalyzed by copper iodide nanoparticles as a recyclable catalyst is described. The advantages of this method are simplicity, shorter reaction time (5-15 min), a cost-effective catalyst, and excellent product isolation (82-92%). N-Boc protection of various structurally diverse aliphatic, aromatic, and heterocyclic amines have been carried out with (Boc)2O with 10 mol% catalyst under pestle mortar grinding under solvent-free conditions. The catalyst possesses distinct advantages, ease of handling as well as removal, cleaner reactions, high activity, and environmentally benign. The final product has been characterised by various spectroscopic techniques. [ABSTRACT FROM AUTHOR]

The design of magnetic hybrid nanomaterials for cooperative activation of diverse functional groups drives future nanocatalysis toward green and sustainable multi‐component organic synthesis. Here, we report the synthesis of unique Ni@CuI hybrid nanocatalysts by oxidation of the Cu0 surface in Ni@Cu core‐shell precursor using an ethanolic I2 solution. The morphological (scanning electron microscopy and energy‐dispersive X‐ray spectroscopy) and structural (powder X‐ray diffraction and X‐ray photoelectron spectroscopy) characterizations conform the formation of Ni0 and CuI hybrid nanocatalysts. These are efficient catalysts for the activation of oxime and olefin substrates to afford spiropyrrolines in a short time and excellent yields under green reaction conditions. The control experiments delineate the role of Cu sites as redox (I–III) triggered cleavage of N−O bond (oximes) and Ni0 sites adsorb the olefin (C=C) which is proximity to the Cu‐enamide intermediate to enhance the intermolecular cyclization lead to spiropyrrolines. The robustness of Ni@CuI hybrid nanocatalyst is demonstrated over five cycles without loss in its turnover and structural integrity, which follows ideal green chemistry metrics. [ABSTRACT FROM AUTHOR]

The solar‐driven photocatalytic reduction of CO2 (CO2RR) into chemical fuels is a promising route to enrich energy supplies and mitigate CO2 emissions. However, low catalytic efficiency and poor selectivity, especially in a pure‐water system, hinder the development of photocatalytic CO2RR owing to the lack of effective catalysts. Herein, we report a novel atom‐confinement and coordination (ACC) strategy to achieve the synthesis of rare‐earth single erbium (Er) atoms supported on carbon nitride nanotubes (Er1/CN‐NT) with a tunable dispersion density of single atoms. Er1/CN‐NT is a highly efficient and robust photocatalyst that exhibits outstanding CO2RR performance in a pure‐water system. Experimental results and density functional theory calculations reveal the crucial role of single Er atoms in promoting photocatalytic CO2RR. [ABSTRACT FROM AUTHOR]

The present paper shows the preparation of a highly porous periodic mesoporous organosilica (PMO) including the ionic liquid pore walls that supported with zinc ions onto PMO-IL (Zn@PMO-IL). Moreover, the material was characterized using field emission‐scanning electron microscopy, transmission electron microscopy, inductively coupled plasma, and N2 adsorption–desorption. Likewise, the catalytic activity of the Zn@PMO-IL, illustrating a highly efficient nanocatalyst for the synthesis of propargylamines through three-component A3-coupling reaction of various aldehydes, amines, and arylacetylene. The results demonstrate an eco-friendly and appealing method with high efficiency and facile work-up procedure. Furthermore, the nanocatalyst can be revived by a simple filtration process and reuse at least five successive runs without considerable reducing in its activity. [ABSTRACT FROM AUTHOR]

Ruthenium nanocatalysis can provide effective deuteration and tritiation of oxazole, imidazole, triazole and carbazole substructures in complex molecules using D2 or T2 gas as isotopic sources. Depending on the substructure considered, this approach does not only represent a significant step forward in practice, with notably higher isotope uptakes, a broader substrate scope and a higher solvent applicability compared to existing procedures, but also the unique way to label important heterocycles using hydrogen isotope exchange. In terms of applications, the high incorporation of deuterium atoms, allows the synthesis of internal standards for LC‐MS quantification. Moreover, the efficacy of the catalyst permits, even under subatmospheric pressure of T2 gas, the preparation of complex radiolabeled drugs owning high molar activities. From a fundamental point of view, a detailed DFT‐based mechanistic study identifying undisclosed key intermediates, allowed a deeper understanding of C−H (and N−H) activation processes occurring at the surface of metallic nanoclusters. [ABSTRACT FROM AUTHOR]

Catalysis of four nanostructures, including graphene oxide nanoribbons (GONR), graphene oxide, N-doped carbon quantum dot and Ca-doped carbon quantum dot is examined on the reaction HAuCl4–trisodium citrate to form nanogold (AuNP). GONR exhibited strongest catalysis and appeared a SERS peak at 1615 cm−1 in the presence of Victoria blue 4R molecular probes in the formed AuNP sol substrate. Upon addition of 4-mercaptophenylboronic acid (MPBA), it adsorbs on GONR to form MPBA–GONR conjugates that caused the SERS peak decreasing due to its catalysis decreasing. Upon addition of glucose, it reacts with MPBA to form MPBA–glucose complex to increase the SERS peak linearly owing to GONR catalysis recovering. The increased SERS signal (ΔI) is linear to glucose concentration in the range of 0.33–5.33 nM, with a detection limit of 0.13 nM. Thus, a new and highly sensitive SERS quantitative analysis method is established for detection of glucose, based on GONR catalytic amplification. [ABSTRACT FROM AUTHOR]

A novel simple green synthesis route was applied to produce copper oxide (CuO) nanoparticles (NPs) and CuO nanograins (NGs) by using cupric chloride dihydrated as copper salt precursor, curcumin (a natural and non‐toxic food spice) as conjugated agent with or without cetyl trimethylammonium bromide acting as a stabilizing agent at extreme basic condition. Synthesis of this curcumin conjugated CuO nanoparticles was optimized by studying effect of several parameters starting with copper salt precursor, curcumin concentration, pH and temperature. Scanning electron microscopy coupled to Energy Dispersive X‐ray Analyzer, thermogravimetirc analysis, X‐ray diffraction, UV‐visible spectroscopy, fluorescence spectroscopy and zeta potential were used to characterize the resulted CuO NPs/NGs. In this work, the synthesized copper oxide nanograins were found to be efficient nano‐catalysts for the reduction of methylene blue and it was found that nanograin has better catalytic activity compared to spherical shape nanoparticles, emphasizing shape of the CuO particles is crucial for its nanocatalytic activity. [ABSTRACT FROM AUTHOR]

We report on the design and testing of new graphite and graphene oxide‐based extended π‐conjugated synthetic scaffolds for applications in sustainable chemistry transformations. Nanoparticle‐functionalised carbonaceous catalysts for new Fischer Tropsch and Reverse GasWater Shift (RGWS) transformations were prepared: functional graphene oxides emerged from graphite powders via an adapted Hummer's method and subsequently impregnated with uniform‐sized nanoparticles. Then the resulting nanomaterials were imaged by TEM, SEM, EDX, AFM and characterised by IR, XPS and Raman spectroscopies prior to incorporation of Pd(II) promoters and further microscopic and spectroscopic analysis. Newly synthesised 2D and 3D layered nanostructures incorporating carbon‐supported iron oxide nanoparticulate pre‐catalysts were tested, upon hydrogen reduction in situ, for the conversion of CO2 to CO as well as for the selective formation of CH4 and longer chain hydrocarbons. The reduction reaction was also carried out and the catalytic species isolated and fully characterised. The catalytic activity of a graphene oxide‐supported iron oxide pre‐catalyst converted CO2 into hydrocarbons at different temperatures (305, 335, 370 and 405 °C), and its activity compared well with that of the analogues supported on graphite oxide, the 3‐dimensional material precursor to the graphene oxide. Investigation into the use of graphene oxide as a framework for catalysis showed that it has promising activity with respect to reverse gas water shift (RWGS) reaction of CO2 to CO, even at the low levels of catalyst used and under the rather mild conditions employed at atmospheric pressure. Whilst the γ‐Fe2O3 decorated graphene oxide‐based pre‐catalyst displays fairly constant activity up to 405 °C, it was found by GC‐MS analysis to be unstable with respect to decomposition at higher temperatures. The addition of palladium as a promoter increased the activity of the iron functionalised graphite oxide in the RWGS. The activity of graphene oxide supported catalysts was found to be enhanced with respect to that of iron‐functionalised graphite oxide with, or without palladium as a promoter, and comparable to that of Fe@carbon nanotube‐based systems tested under analogous conditions. These results display a significant step forward for the catalytic activity estimations for the iron functionalised and rapidly processable and scalable graphene oxide. The hereby investigated phenomena are of particular relevance for the understanding of the intimate surface morphologies and the potential role of non‐covalent interactions in the iron oxide‐graphene oxide networks, which could inform the design of nano‐materials with performance in future sustainable catalysis applications. [ABSTRACT FROM AUTHOR]

Heavy naphtha reforming, a crucial downstream process in oil refineries for improving the octane number of the gasoline feedstock, requires expensive Pt metal catalysts and it accounts for 60% of the catalyst cost. These conventional Pt nanoparticle sizes range between 1 – 2 nm and thus, only ≈ 80% of the Pt atoms of the particle are available for the catalytic reactions. In this work, we hypothesized that it might be possible to achieve 100% atom utilization if the Pt atoms are distributed as single or pseudo-single atom clusters, where all the atoms are exposed to the reactant molecules and by tuning their Interfacial Interactions. We aimed to significantly reduce the Pt contents by dispersing the active Pt sites as pseudo-single atoms on industrially relevant γ-Al 2 O 3 support. Interfacial Interactions and stability of Pt sites were then tuned by using tin (Sn) as a promoter. These catalysts were then evaluated for heavy naphtha reforming in a fixed-bed reactor. The catalyst with Sn/Pt mole ratio of 1.68 showed excellent performance with aromatics of 83 wt% and research octane number (RON) of ≈ 103. These results indicated our catalyst preparation methodologies and interfacial interaction tuning successfully disperse Pt on the spherical alumina support leading to better atom economy. With 30–50% less Pt content when compared to the industrially used catalyst, made the heavy naphtha reforming process economical and sustainable. [Display omitted] [ABSTRACT FROM AUTHOR]

Exploiting biomass to synthesise compounds that may replace fossil-based ones is of high interest in order to reduce dependence on non-renewable resources. 1,2-pentanediol and 1,5-pentanediol can be produced from furfural, furfuryl alcohol or tetrahydrofurfuryl alcohol following a metal catalysed hydrogenation/C-O cleavage procedure. Colloidal ruthenium nanoparticles stabilized with polyvinylpyrrolidone in situ modified with different organic compounds are able to produce 1,2-pentanediol directly from furfural in a 36% of selectivity at 125 °C under 20 bar of H2 pressure.

Aihui Liang,1,2,* Chongning Li,1,2,* Dan Li,1,2,* Yanghe Luo,1–3 Guiqing Wen,1,2 Zhiliang Jiang1,2 1Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, 2Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin, 3School of Food and Bioengineering, Hezhou University, Hezhou, China *These authors contributed equally to this work Abstract: The nanogold reaction between HAuCl4 and citrate is very slow, and the catalyst graphene oxide nanoribbon (GONR) enhanced the nanoreaction greatly to produce gold nanoparticles (AuNPs) that exhibited strong surface plasmon resonance (SPR) absorption (Abs) at 550 nm and resonance Rayleigh scattering (RRS) at 550 nm. Upon addition of the peptide of human chorionic gonadotropin (hCG), the peptide could adsorb on the GONR surface, which inhibited the catalysis. When hCG was added, peptides were separated from the GONR surface due to the formation of stable peptide–hCG complex, which led to the activation of GONR catalytic effect. With the increase in hCG concentration, the RRS and Abs signal enhanced linearly. The enhanced RRS value showed a good linear relationship with hCG concentration in the range of 0.2–20 ng/mL, with a detection limit of 70 pg/mL. Accordingly, two new GONR catalytic RRS/Abs methods were established for detecting hCG in serum samples. Keywords: nanocatalysis, graphene oxide nanoribbon, peptide regulation, hCG, RRS

Nanosized Mg-doped ceria powders were obtained by self-propagating room temperature reaction without using surfactants or templates. X-ray diffraction analysis and field emission scanning microscopy results showed that the doped samples are solid solutions with fluorite-type structure and spherical morphology. Raman spectra revealed an increase in the amount of oxygen vacancies with the increase of Mg concentration. This increasing results in a narrowing of the bandgap of CeO2. The photocatalytic performances of the Mg-doped ceria solid solutions were evaluated by decomposing an organic dye, crystal violet under UV irradiation. The Mg-doped ceria solid solutions exhibit significantly better photocatalytic activity than the pure CeO2 and commercial TiO2. The higher first rate constant of the Mg-doped samples demonstrated that they are much more efficient than TiO2 and CeO2 under UV light. Mg2+ dopant ions and oxygen vacancies play a significant role in the enhancement of photocatalytic performances of the Mg-doped ceria.

Catalytic cancer therapy targets cancer cells by exploiting the specific characteristics of the tumor microenvironment (TME). TME-based catalytic strategies rely on the use of molecules already present in the TME. Amino groups seem to be a suitable target, given the abundance of proteins and peptides in biological environments. Here we show that catalytic CuFe 2 O 4 nanoparticles are able to foster transaminations with different amino acids and pyruvate, another key molecule present in the TME. We observed a significant in cellulo decrease in glutamine and alanine levels up to 48 h after treatment. In addition, we found that di- and tripeptides also undergo catalytic transamination, thereby extending the range of the effects to other molecules such as glutathione disulfide (GSSG). Mechanistic calculations for GSSG transamination revealed the formation of an imine between the oxo group of pyruvate and the free -NH 2 group of GSSG. Our results highlight transamination as alternative to the existing toolbox of catalytic therapies.

Nanozyme mediated catalytic therapy is an attractive strategy for cancer therapy. However, the nanozymes are tended to assemble into 3D architectures, resulting in poor catalytic efficiency for therapy. This study designs the assembly of nanozymes and natural enzymes into the layered structures featuring hexagonal pores as nanozyme clusterphene and investigates their catalytic therapy with the assistance of electric field. The nanozyme-based clusterphene consists of polyoxometalate (POM) and natural glucose oxidase (GOx), named POMG-based clusterphene, which facilitate multi-enzyme activities including peroxidase (POD), catalase (CAT), and glutathione oxidase (GPx). The highly ordered layers with hexagonal pores of POMG units significantly improve the peroxidase-like (POD-like) activity of the nanozyme and thus the sustained production of reactive oxygen species (ROS). At the same time, GOx can increase endogenous H 2 O 2 and produce gluconic acid while consuming glucose, the nutrient of tumor cell growth. The results indicate that the POD-like activity of POMG-based clusterphene increase approximately sevenfold under electrical stimulation compared with Nd-substituted keggin type POM cluster (NdPW 11 ). The experiments both in vitro and in vivo show that the proposed POMG-based clusterphene mediated cascade catalytic therapy is capable of efficient tumor inhibiting and preventing tumor proliferation in tumor-bearing mice model, promising as an excellent candidate for catalytic therapy., (© 2024 Wiley‐VCH GmbH.)

The insertion of copper into the gold lattice forming gold–copper (AuCu) nanoalloys enhances the gold catalytic performance in reactions such as CO oxidation. Here, we compared the catalytic performance of 6 nm AuCu nanoparticles (NPs) supported on SiO2 (AuCu_SiO2), a nonreducible oxide, and CeO2 (AuCu_CeO2), a reducible one, under preferential oxidation of CO (CO-PROX). Under reaction conditions, the support nature impacted on the stabilization of different species on the catalyst surface. The AuCu_CeO2 was both more active and more stable, which was associated with the ability of CeO2 to stabilize the AuCu alloy phase under reaction conditions. [ABSTRACT FROM AUTHOR]

Acid functionalization of a carbon support allows to enhance the electrocatalytic activity of Pd to hydrogenate benzaldehyde to benzyl alcohol proportional to the concentration of Brønsted‐acid sites. In contrast, the hydrogenation rate is not affected when H2 is used as a reduction equivalent. The different responses to the catalyst properties are shown to be caused by differences in the hydrogenation mechanism between the electrochemical and the H2‐induced hydrogenation pathways. The enhancement of electrocatalytic reduction is realized by the participation of support‐generated hydronium ions in the proximity of the metal particles. [ABSTRACT FROM AUTHOR]

With an attempt to improve the efficiency and stability of photocatalysts for hydrogen evolution through the water-splitting reaction, wide varieties of photocatalysts including a series of SrTiO SB 3 sb catalysts, carbon nitride catalysts, MoP SB 4 sb co-catalysts,[17] and other photocatalysts have been developed and examined. The contributions in this special issue can be categorized into two main research themes principally in catalyst modification/functionalization for water splitting reaction products (a series of SrTiO SB 3 sb catalysts, a series of carbon nitride catalysts, MoP SB 4 sb co-catalyst, and other water splitting photocatalysts) and other photocatalytic reactions for sustainable chemical production (Figure). Among a series of SrTiO SB 3 sb photocatalysts, Han I et al i . used gold plasmon-enhanced SrTiO SB 3 sb /TiO SB 2 sb photocatalyst for solar hydrogen production.[7] They found that the catalyst could enhance photocatalytic hydrogen production for 75-fold by the internal electric field between the interfaces of SrTiO SB 3 sb /TiO SB 2 sb . Furthermore, Zhao I et al i . suggested that the photocatalytic hydrogen evolution can be highly improved by constructing 0D FeP Nanodots/2D g-C SB 3 sb N SB 4 sb nanosheets heterojunction.[10] These novel composite heterojunctions, successfully fabricated by a two-step approach, revealed highly enhanced solar-driven photocatalytic hydrogen evolution efficiency without using Pt-based co-catalyst. [Extracted from the article]