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Magnetic property (e.g. spin order) of support is of great importance in the rational design of heterogeneous catalysts. Herein, we have taken the Ni-supported ferromagnetic (FM) CrBr3 support (Nix/CrBr3) to thoroughly investigate the effect of spin-order on electrocatalytic oxygen reduction reaction (ORR) via spin-polarized density functional theory calculations. Specifically, Ni loading induces anti-FM coupling in Ni–Cr, leading to a transition from FM-to-ferrimagnetic (FIM) properties, while Ni–Ni metallic bonds create a robust FM direct exchange, benefiting the improvement of the phase transition temperature. Interestingly, with the increase in Ni loading, the easy magnetic axis changes from out-of-plane (2D-Heisenberg) to in-plane (2D-XY). The adsorption properties of Nix/CrBr3, involving O2 adsorption energy and configuration, are not governed by the d-band center but strongly correlate with magnetic anisotropy. It is noteworthy that the applied potential and electrolyte acidity triggers spin-order transition phenomena during the ORR and induces the catalytic pathway change from 4e− ORR to 2e− ORR with the excellent onset potential of 0.93 V/reversible hydrogen electrode, comparable to the existing most excellent noble-metal catalysts. Generally, these findings offer new avenues to understand and design heterogeneous catalysts with magnetic support. [ABSTRACT FROM AUTHOR]

The trend today is transformation of traditional high-carbon fossil fuel energy to low-carbon clean energy. A promising energy carrier is hydrogen generated from renewable energy sources, providing that hydrogen storage and transportation are the primary important parts of hydrogen energy industrial chain. Efficient and reversible hydrogen storage is of crucial importance in the application of hydrogen energy, and the use of liquid organic hydrogen carriers (LOHC) for hydrogen storage is among technologies under development. Highly effective and low-cost catalysts are of prime importance in the LOHC technology. The present review elucidates the directions and advancements in the development of Pd catalysts for dehydrogenation/hydrogenation of heterocyclic LOHC compounds for the last few years including 2024. The review provides valuable insights into the design and preparation of efficient and durable heterogeneous Pd catalysts for the complete reversible dehydrogenation of hydrogen-rich heterocyclic molecules that are considered as LOHC, which can contribute to technologies based on hydrogen production and storage. Thermodynamic aspects of the use of N-heterocyclic compounds and results of theoretical studies of LOHC processing on Pd catalysts are considered. • Recent 5 years summary on Pd catalysts for H 2 release from heteroaromatic LOHC. • Variation in the catalyst efficiency depending on the Pd state and content is discussed. • Effect of the support nature and reducibility on the catalyst efficiency is analyzed. • Application of catalysts with a low Pd content for different LOHC was shown. • Pd clusters and nanoparticles of 1–4 nm on reducible supports are promising catalysts. [ABSTRACT FROM AUTHOR]

Three 1D coordination polymers (CPs), {[CuL2(H2O)] ⋅ (H2O)3}n(1) {[CoL2(H2O)2] ⋅ (H2O)}n(2) and {[NiL2(H2O)] ⋅ (H2O)3}n(3), (L1=N‐nicotinoylglycinato) have been synthesized by adopting a solvothermal reaction strategy and characterized through several spectral techniques i. e. elemental analyses, FT‐IR, TGA, EDX, DSC, AAS, and PXRD. X‐ray single crystal analysis revealed the 5‐, 6‐ and 7‐coordinated structures respectively for CPs 1, 2 and 3 wherein, L1 connects the metal ions in a bridging mode. The CPs entail H‐bonding, π–π stacking along with other non‐covalent interactions and expand into 3D supramolecular networks. Further, FESEM and HRTEM provided morphological insight for 1–3 and aid in obtaining interplanar spacings. CPs 1–3 possessing distinct coordination numbers and good thermal stability have been subjected to catalysis after optimization and notably, these serve as efficient, easy to work up, and reusable porous heterogeneous catalysts for Henry and Morita‐Baylis‐Hillman (MBH) reactions with reasonably good yields (97–93 %). Remarkably, catalyzed by 1–3 can be reused at least seven times for the Henry reaction and six times for the MBH reaction, retaining their catalytic efficiency. Relative catalytic efficacy toward the Henry and MBH reactions follows the order 1>2>3. Present findings are based on a rational approach of varying coordination number (5, 6 and 7) and metal ions [Cu(II), Co(II) and Ni(II)] respectively in 1–3 having structural evidence and examine their catalytic performances for typical Henry and MBH reactions. [ABSTRACT FROM AUTHOR]

An atom‐economical sequential‐flow synthesis of donepezil, a widely prescribed drug for Alzheimer's disease, was accomplished using inexpensive, commercially available precursors. This achievement was made possible by reconfiguring the synthetic route to include only heterogeneous catalytic addition and condensation reactions, with a particular emphasis on skeletal transformation and bond formation through hydrogenation processes. Notably, water was the sole byproduct in this synthesis. A crucial aspect of this work was the development of appropriate continuous‐flow processes to achieve a one‐flow synthesis. This was accomplished by implementing in‐line treatments of the main reaction stream to eliminate inhibitory factors that could affect catalyst performance in the hydrogenation steps. [ABSTRACT FROM AUTHOR]

Herein, a heterogeneous structure of Ni–Mo catalyst comprising Ni4Mo nanoalloys decorated on a MoOx matrix via electrodeposition is introduced. This catalyst exhibits remarkable hydrogen evolution reaction (HER) activity across a range of pH conditions. The heterogeneous Ni–Mo catalyst showed low overpotentials only of 24 and 86, 21 and 60, and 37 and 168 mV to produce a current density of 10 and 100 mA cm−2 (η10 and η100) in alkaline, acidic, and neutral media, respectively, which represents one of the most active catalysts for the HER. The enhanced activity is attributed to the hydrogen spillover effect, where hydrogen atoms migrate between the Ni4Mo alloys and the MoOx matrix, forming hydrogen molybdenum bronze as additional active sites. Additionally, the Ni4Mo facilitated the water dissociation process, which helps the Volmer step in the alkaline/neutral HER. Through electrochemical analysis, in situ Raman spectroscopy, and density functional theory calculations, the fast HER mechanism is elucidated. [ABSTRACT FROM AUTHOR]

Ethylene dimerization is an industrial process that is currently carried out using homogeneous catalysts. Here we present a highly active heterogeneous catalyst containing minute amounts of atomically dispersed Pd. It requires no co‐catalyst(s) or activator(s) and significantly outperforms previously reported catalysts tested under similar reaction conditions. The selectivity to C4‐ and C6‐hydrocarbons was about 80 % and 10 % at 42 % ethylene conversion at 200 °C using an industrially relevant feed containing 50 vol % ethylene, respectively. Our kinetic and catalyst characterization experiments complemented by density functional theory calculations provide molecular insights into the local environment of isolated Pd(II)Ox species and their role in achieving high activity in the target reaction. When the developed catalyst was rationally integrated with a Mo‐containing olefin metathesis catalyst in the same reactor, the formed butenes reacted with ethylene to propylene with a selectivity of 98 % at about 24 % ethylene conversion. [ABSTRACT FROM AUTHOR]

Polyolefins such as polyethylenes and polypropylenes are the most‐produced plastic waste globally, yet are difficult to convert into useful products due to their unreactivity. Pyrolysis is a practical method for large‐scale treatment of mixed, contaminated plastic, allowing for their conversion into industrially‐relevant petrochemicals. Metal–organic frameworks (MOFs), despite their tremendous utility in heterogeneous catalysis, have been overlooked for polyolefin depolymerization due to their perceived thermal instabilities and inability of polyethylenes and polypropylenes to penetrate their pores. Herein, we demonstrate the viability of UiO‐66 MOFs containing coordinatively‐unsaturated zirconium nodes, as effective catalysts for pyrolysis that significantly enhances the yields of valuable liquid and gas hydrocarbons, whilst halving the amounts of residual solids produced. Reactions occur on the Lewis‐acidic UiO‐66 nodes, without the need for noble metals, and yield aliphatic product distributions distinctly different from the aromatic‐rich hydrocarbons that can be obtained from zeolite catalysis. We also demonstrate the first unambiguous characterization of polyolefin penetration into UiO‐66 pores at pyrolytic temperatures, allowing access to the abundant Zr‐oxo nodes within the MOF interior for efficient C−C cleavage. Our work highlights the potential of MOFs as highly‐designable heterogeneous catalysts for depolymerisation of plastics, which can complement conventional catalysts in reactivity. [ABSTRACT FROM AUTHOR]

Acid catalysis plays a pivotal role in the industrial landscape due to its multifaceted contributions to various chemical processes in numerous sectors, including petrochemicals, polymers, food processing, and biodiesel production, among others. Sulfonated graphenes hold notable relevance as heterogeneous acid catalysts due to their unique combination of graphene's structural properties and the introduction of sulfonic groups as catalytic acid sites. Herein, we report the preparation of three sulfonated graphene‐based materials – sulfonated reduced graphene oxide (rGO‐SO3H), chlorosulfonated reduced graphene oxide (rGO‐HSO3Cl) and sulfonated graphene oxide (GO‐SO3H) – by different synthetic approaches. Physicochemical, textural, morphological, and acidic properties of all materials were characterized in detail by different instrumental techniques. Innovatively, these materials have been evaluated as heterogeneous acid catalysts in the solketal synthesis by acetalization of glycerol, which is considered an interesting building block to produce added‐value products. The density of acidic active sites and hydrophobicity were found to be conditioning parameters of the resulting catalytic activity in terms of conversion and selectivity. The best catalytic performance was obtained by rGO‐SO3H, reaching the maximum conversion towards solketal in 15 minutes under mild reaction conditions. The reusability and stability of all materials were also examined after three consecutive acetalization reactions with only a slight loss of catalytic activity. [ABSTRACT FROM AUTHOR]

The catastrophic ramifications of fossil fuels on the environment have prompted the search for renewable energy sources. Over the recent decades, biodiesel has garnered attention as a promising direct alternative to diesel fuel; however, reliance on homogeneous catalysts and the requirement for refined vegetable oil feedstocks present financial and sustainability concerns. Thus, there exists a need for the development of sustainable and cost‐effective catalytic solutions. Herein, the application of lignin, an abundant and renewable biomass, as an effective heterogeneous catalyst is reported for biodiesel production via the esterification of oleic acid. Lignin is extracted from corn straw using sulfuric acid, which endows sulfonic acid groups (0.85 mmol g−1) to its structure allowing it to act as an acid catalyst without additional post‐treatments. Conversion of oleic oil to biodiesel is achieved at 97% using a 1:3 oleic acid to methanol molar ratio with a 5 wt.% catalyst loading at 90 °C after only 30 min. Moreover, the catalyst exhibits a remarkable turnover frequency of 2.61 min−1 proving its efficiency. These findings demonstrate that heterogeneous catalysts can be prepared from biomass waste offering a significantly cheaper and less intensive synthesis process and allowing for a paradigm shift to non‐edible and waste cooking oils. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2 reduction (ECR) powered by renewable electricity is a promising technology to mitigate carbon emissions and lessen the dependence on fossil fuels toward a carbon‐neutral energy cycle. Metal–organic frameworks (MOFs) and their derivatives, due to their excellent intrinsic activity, have emerged as promising materials for the ECR to high‐demand products. However, challenges such as unsatisfactory energy efficiency, selectivity, and relatively low production rates hinder their industrial scalability. Here, a comprehensive and critical review is presented that summarizes the state‐of‐the‐art progress in MOF‐based and MOF‐derived CO2 electroreduction catalysts from design and functionality perspectives. The fundamentals of CO2 reduction reaction (CO2RR) over heterogeneous catalysts, reaction mechanisms, and key challenges faced by ECR are described first to establish a solid foundation for forthcoming in‐depth analyses. MOF's building blocks, properties, and shortcomings pertinent to ECR including low conductivity and stability, are systematically discussed. Moreover, comprehensive discussions are provided on MOF‐based and MOF‐derived catalysts design, fabrication, characterization, and CO2RR activity to pinpoint the intricate structure‐property‐performance relationship. Finally, promising recommendations are put forward for enhancing MOF electrocatalysts activity, selectivity, and durability. This work may serve as a guideline for developing high‐performance MOF‐related catalysts for CO2RR, benefiting researchers working in this growing and potentially game‐changing area. [ABSTRACT FROM AUTHOR]

Cu immobilized onto N-doped carbon spheres (Cu/N-doped CS) derived from soybean flour was synthesized via the hydrothermal method and certified as a green high-efficiency catalyst for the regioselective synthesis of 1,4-disubstituted 1H-1,2,3-triazoles. The obtained N-doped carbon spheres from a combination of glucose and soy flour have a larger size and suitable affinity for load copper species. The morphology and structure of the as-prepared catalyst have been confirmed based on FT-IR, XRD, FE-SEM, EDX, BET, and ICP-OES characterizations. The catalytic performance of the Cu/N-doped carbon spheroids was investigated experimentally. It was found that the Cu/N-doped CS nanocomposite has a high efficiency and recyclability for 5 cycles without any appreciable loss in its catalytic activity in the synthesis of 1,4-disubstituted 1H-1,2,3-triazoles via the three-component condensation reaction of various epoxide/alkyl or aryl halides, sodium azide, and phenylacetylene in a water medium. Furthermore, significant advantages such as stability, ease of preparation, low cost of the carbon resource, high regioselectivity, and good product yield have been achieved in the heterogeneous catalyst system attractive for large-scale in many industrial products. [ABSTRACT FROM AUTHOR]

The anthracene‐appended Schiff base N1‐(anthracene‐9‐methylene)benzene‐1,2‐diamine and its Cu(II) complex has been synthesized and anchored on MCM‐41 support (MCM@CP@AnL@Cu 1). The synthesized catalyst was characterized by various analytical techniques including single crystal X‐ray. Malononitrile, 1,3‐dione, and aromatic aldehydes with various substituents were used in one‐pot, three‐component synthesis of 2‐amino‐3‐cyano‐4H‐pyran/chromene derivatives using above catalyst 1. All the products of the catalytic reaction were characterized by 1H and 13C NMR spectra. We have also proposed a probable reaction mechanism involved in the catalytic reaction. The present catalyst has several advantages like works in mild reaction conditions, that is, at 80 °C, gives higher yields up to 97%, has thermal stability up to 295 °C, and can be reused up to 5 cycles. The immobilized material did not show any considerable leaching or deterioration throughout the catalytic reactions, confirming that it possesses a practical benefit over homogeneous catalysis. The MCM@CP@AnL@Cu (1) is believed to be a good solid heterogeneous catalyst and meets the need of green chemistry for sustainable environment. To the best of our knowledge, this is first example of anthracene‐based Cu (II)‐Schiff base complexes immobilized on modified MCM‐41 surfaces for the multicomponent synthesis of 4H‐pyrans. [ABSTRACT FROM AUTHOR]

The design and development of new high-performance catalysts is one of the most important and challenging issues to achieve sustainable chemical and energy production. This Feature Article describes the synthesis of nanostructured metal oxides and phosphates mainly based on earth-abundant metals and their thermocatalytic application to selective oxidation and acid–base reactions. A simple and versatile methodology for the control of nanostructures based on crystalline complex oxides and phosphates with diverse structures and compositions is proposed as another approach to catalyst design. Herein, two unique and verstile methods for the synthesis of metal oxide and phosphate nanostructures are introduced; an amino acid-aided method for metal oxides and phosphates and a precursor crystallization method for porous manganese oxides. Nanomaterials based on perovskite oxides, manganese oxides, and metal phosphates can function as effective heterogeneous catalysts for selective aerobic oxidation, biomass conversion, direct methane conversion, one-pot synthesis, acid–base reactions, and water electrolysis. Furthermore, the structure–activity relationship is clarified based on experimental and computational approaches, and the influence of oxygen vacancy formation, concerted activation of molecules, and the redox/acid–base properties of the outermost surface are discussed. The proposed methodology for nanostructure control would be useful not only for the design and understanding of the complexity of metal oxide catalysts, but also for the development of innovative catalysts. [ABSTRACT FROM AUTHOR]

Development of heterogeneous catalyst is significant key for achieving high performance of NaBH 4 hydrolysis to produce hydrogen. The stability of sodium borohydride in the presence of suitable catalyst is the efficient method to generate hydrogen. In this work, styrene-imid PIILP, polymer 1 decorated styrene, imidazolium ionic liquid, and cross-coupling is successfully synthesised by AIBN initiated radical polymerisation, then precipitation with 3,3′,3″phosphinetriyltribenzene sulfonate with ratio (1:0.3) to isolate the first styrene-imid- sulphonated PIILP, polymer 2. RuNP@styrene-imid-sulphonated PIILP, RuNPs catalyst 3 was synthesised by impregnation with RuCl 3 , then reduction by NaBH 4. Moreover, several analytical techniques such as, 31P, 1H, 13C solid-state NMR, CHN, IR, XPS, TEM, TGA-DTA, and SEM were examined to explore the obtained catalyst 3. The hydrogen generation from NaBH 4 utilizing catalyst 3 was exhibited the catalytic behaviour studying several parameters such as, temperature, catalytic loading, and NaBH 4 concentrations this work was deducted the activation energy (30.32 kJmol-1), and the turnover frequency (TOF) reached up 134.9, 112.77, and 98.38 moleH 2.mol cat −1.min−1 at 40, 35 and 30 °C. The effectiveness of Ruthenium nanoparticle catalyst 3 for the hydrolysis reaction of NaBH 4 was examined in H 2 O and D 2 O resulting kinetic isotope effect (KIE) k H /k D = 3. In addition, RuNPs demonstrated a promising efficient for reuse catalyst 3 after five cycles for the catalytic hydrolysis. [Display omitted] • RuNPs was synthesised and characterised by 31P and 13C Solid-State NMR, CHN, XPS, TEM, SEM, TGA and FT-IR. • A TOF 134.9 mole H2.mol cat −1.min−1 for RuNPs@styrene-imid-sulphonated PIILP was achieved. • E a of 30.32 for RuNPs@styrene-imid-sulphonated PIILP were achieved. • RuNPs demonstrated a promising efficiency for reuse RuNPs after five cycles for the catalytic hydrolysis. [ABSTRACT FROM AUTHOR]

Upcycling of plastic waste to low carbon fuels remains technologically challenging. This study presents near-supercritical catalytic hydrothermal conversion of automotive, marine, agricultural and model plastic wastes to hydrogen and value-added products. At 350 °C, 3000–3300 psi and 1 h of reaction time using a sodium hydroxide catalyst, the hydrothermal conversion of plastic wastes produced between 23 and 76 g of hydrogen per kg of feedstock with few other gases present. The activation energy of the plastic gasification reaction was found to be 6.38–6.83 kJ/mol through the 1 h unsteady state hydrothermal ramping at average of 5.5 °C/min. The highly contaminated, heterogeneous automotive fluff (AF) containing polymeric and natural fiber waste, had the highest hydrogen production of 76 g(H 2)/kg(feed) and was further evaluated with additional alkali and non-precious metal catalysts. Alkali catalysts increased hydrogen production in the following order: NaOH > KOH > K 2 CO 3 and were more effective than non-precious metal catalysts whose order was Fe/MCM41 > Ni/SiAl > Fe/ZSM-5. The use of non-precious metal and no catalyst led to mainly CO and CO 2 production, reaching 1251 g(CO 2)/kg(feed) with no hydrogen produced using the Fe/ZSM-5 catalyst. Valuable chemical products including phenol, cresols, guaiacol, and straight chain alkanes dominated the oil phase. The solid analysis revealed new and enhanced peak intensities in the hydrochar functional groups that were absent in the feedstocks. Regular spherical, hexagonal, and cylindrical structural surface morphologies showed varying amounts of carbon and inorganic elements. This work highlights a viable technology for safe upcycling of challenging waste. • Low carbon hydrogen and organics are produced from end-of-life plastic waste. • Random carbon-carbon scission propagates hydrothermal reaction mechanisms. • Alkali catalysts cracks heterogeneous plastic waste to more hydrogen. • Non-precious metal catalysts cracks waste to hydrochar of high surface area. [ABSTRACT FROM AUTHOR]

Heterobimetallic complexes are studied for their ability to mimic biological systems as well as active sites in heterogeneous catalysts. While specific interest in early/late heterobimetallic systems has fluctuated, they serve as important models to fundamentally understand metal–metal bonding. Specifically, the polarized metal–metal multiple bonds formed in highly reduced early/late heterobimetallic complexes exemplify how each metal modulates the electronic environment and reactivity of the complex as a whole. In this Perspective, we chronicle the development of phosphinoamide-supported group IV/cobalt heterobimetallic complexes. This combination of metals allows access to a low valent Co−I center, which performs a rich variety of bond activation reactions when coupled with the pendent Lewis acidic metal center. Conversely, the low valent late transition metal is also observed to act as an electron reservoir, allowing for redox processes to occur at the d0 group IV metal site. Most of the bond activation reactions carried out by phosphinoamide-bridged M/Co−I (M = Ti, Zr, Hf) complexes are facilitated by cleavage of metal–metal multiple bonds, which serve as readily accessible electron reservoirs. Comparative studies in which both the number of buttressing ligands as well as the identity of the early metal were varied to give a library of heterobimetallic complexes are summarized, providing a thorough understanding of the reactivity of M/Co−I heterobimetallic systems. [ABSTRACT FROM AUTHOR]

We present the use of an amine functionalized two-dimensional clay i.e., aminoclay (AC), in the chemistry of a three-dimensional metal–organic framework (MOF) i.e., MIL-101(Cr), to prepare MIL-101(Cr)/AC composites, which are exploited as catalysts for efficient conversion of CO2 gas into cyclic carbonates under ambient reaction conditions. Three different MOF nanocomposites, denoted as MIL-101(Cr)/AC-1, MIL-101(Cr)/AC-2, and MIL-101(Cr)/AC-3, were synthesized by an in situ process by adding different amounts of AC to the precursor solutions of the MIL-101(Cr). The composites were characterized by various techniques such as FT-IR, PXRD, FESEM, EDX, TGA, N2 adsorption, as well as CO2 and NH3-TPD measurements. The composites were exploited as heterogeneous catalysts for CO2 cycloaddition reactions with different epoxides and the catalytic activity was investigated at atmospheric pressure under solvent-free conditions. Among all the materials, MIL-101(Cr)/AC-2 shows the best catalytic efficiency under the optimized conditions and exhibits enhanced efficacy compared to various MIL-101(Cr)-based MOF catalysts, which typically need either high temperature and pressure or a longer reaction time or a combination of all the parameters. The present protocol using MIL-101(Cr)/AC-2 as the heterogeneous catalyst gives 99.9% conversion for all the substrates into the products at atmospheric pressure. [ABSTRACT FROM AUTHOR]

5‐Hydroxymethylfurfural (5‐HMF) derived from lignocellulose represents an important platform molecule that could be employed in the selective hydrogenation of the furan ring to prepare 5‑hydroxymethyltetrahydrofurfural (HMTHF). However, the reported catalytic systems for the synthesis of HMTHF using 5‐HMF still require additional hydrogen pressure. In this study, the Pd/ZrO2 catalyst with uniformly dispersed Pd nanoparticles was prepared via a simple impregnation reduction process. This catalyst exhibited excellent catalytic activity and selectivity for the hydrogenation of 5‐HMF to HMTHF. High HMTHF yields up to 92.3% were produced under mild reaction conditions of ambient hydrogen pressure and room temperature in methanol solvent. This result was superior to the most catalytic systems that had been reported so far. The mechanism study revealed that the active hydrogen species on the surface of the Pd nanoparticles and the reaction solvent in this study were the pivotal factors influencing the hydrogenation of furan rings in 5‐HMF. [ABSTRACT FROM AUTHOR]

ABSTRACT Exploring the relationship between the structure of active site and the activity in molecular level and investigating the reason for deactivation are extremely important in designing the highly active catalyst. In this paper, new self‐assembly Schiff‐base Pd/Cu nanosheets supported on the surface of graphene oxide (GO) (called as GO@Hpmaba‐Pd/Cu) were fabricated and characterized. Among them, GO@Hpmaba‐Pd0.2/Cu0.8 exhibited a high activity with a TOF value of up to 95,357 h−1 and substrate suitability in Suzuki cross‐coupling reaction. GO@Hpmaba‐Pd0.2/Cu0.8 could be reused at least 13 times. GO@Hpmaba‐Pd0.2/Cu0.8 was a heterogeneous catalyst and the catalysis occurred on the surface. The truly active sites included Pd/PdO/CuO/PdCu3 formed in situ on the surface of the hetero‐organometallic Pd/Cu nanosheet during catalysis. The synergistic effects among these active sites could be described as that the electrons transferred from GO to CuO (PdO) or to Pd via ligand (Hpmaba) and subsequently electrons transferred from CuO (PdO) to Pd. These made more electron negative palladium, enhancing the oxidation addition between palladium and aryl halide and prompting the activity. The deactivation of catalyst was mainly caused by some destroyed organometallic in the nanosheet, residues adsorbed on catalytic surface, loss of active Pd due to the leaching with increase of recycling, and the aggregation of active metals. [ABSTRACT FROM AUTHOR]

Recent advances in solid‐state nuclear magnetic resonance (NMR) spectroscopy, combined with dynamic nuclear polarization (DNP), quantum chemical DFT calculations, and gas‐phase NMR spectroscopy investigating the structure and reactivity of heterogeneous catalysts are reviewed. The investigated catalysts range from classical mononuclear catalysts, like immobilized derivates of Wilkinson's catalysts over binuclear catalysts such as the dirhodium paddlewheel catalyst to catalytic nanoparticles, employing various support materials, such as mesoporous silica gels, coordination polymers, and biomaterials such as cellulose. [ABSTRACT FROM AUTHOR]

In this study, we present a novel method for synthesising zinc oxide nanoparticles (ZnO NPs) from the dried Caesalpinia sappan seeds powder. Comprehensive characterisation using XRD, FTIR, SEM, and EDX techniques was employed to elucidate the surface and morphological properties of these ZnO NPs. We showcase the versatile application of ZnO NPs as heterogeneous catalyst in the synthesis of 5-arylmethylidene-pyrimidin-2,4,6-triones. Notably, this eco-friendly approach eliminates the need for organic solvents, offering a sustainable route to producing 5-arylmethylidene-pyrimidin-2,4,6-triones in high yields. Furthermore, we investigate the corrosion inhibition properties of ZnO NPs on mild steel in 5% sodium chloride solution. Our findings reveal the ZnO NPs’ significant inhibition efficiency against corrosion, promising potential for practical applications. In addition to their chemical applications, we delve into the biological activities of ZnO NPs, including their antibacterial effects against both Gram-positive and Gram-negative bacteria, anti-oncogenic activity against DU-145 cells, and scavenging activities against oxidative stress. [ABSTRACT FROM AUTHOR]

The direct construction of metal‐free catalysts on conductive substrates for electrocatalytic organic hydrogenation reactions is significant but still unexplored. Here, learning from the homogeneous molecular catalysts, an organic molecular mimetic metal‐free heterogeneous catalyst is designed and constructed in situ on a graphite flake electrode via a mild electrochemical oxidation‐reduction relay strategy. The as‐prepared −COOH‐ and −OH‐functionalized metal‐free catalyst exhibits an electrocatalytic alkyne semihydrogenation performance with a 72 % Faradaic efficiency, 99 % selectivity and 96 % yield of the alkene product, which is comparable to that of noble metal catalysts. The removal of these oxygen‐containing groups leads to negligible activity. The experimental and calculation results reveal that the origin of the high activity can be assigned to the −COOH and −OH groups on graphite. A flow electrolytic cell delivers ten grams of hydrogenated products with 81 % Faradaic efficiency. This metal‐free catalyst is also suitable for gas‐phase acetylene semihydrogenation and other electrocatalytic hydrogenation reactions. [ABSTRACT FROM AUTHOR]

Precisely controlling the microstructure of supported metal catalysts and regulating metal‐support interactions at the atomic level are essential for achieving highly efficient heterogeneous catalysts. Strong metal‐support interaction (SMSI) not only stabilizes metal nanoparticles and improves their resistance to sintering but also modulates the electrical interaction between metal species and the support, optimizing the catalytic activity and selectivity. Therefore, understating the formation mechanism of SMSI and its dynamic evolution during the chemical reaction at the atomic scale is crucial for guiding the structural design and performance optimization of supported metal catalysts. Recent advancements in in situ transmission electron microscopy (TEM) have shed new light on these complex phenomena, providing deeper insights into the SMSI dynamics. Here, the research progress of in situ TEM investigation on SMSI in heterogeneous catalysis is systematically reviewed, focusing on the formation dynamics, structural evolution during the catalytic reactions, and regulation methods of SMSI. The significant advantages of in situ TEM technologies for SMSI research are also highlighted. Moreover, the challenges and probable development paths of in situ TEM studies on the SMSI are also provided. [ABSTRACT FROM AUTHOR]

ZSM-5, an efficient and reusable heterogeneous catalyst, is employed for the one-pot, three-component synthesis of 2,4,6-triarylpyridines from substituted benzaldehydes, acetophenones and ammonium acetate using a simple, efficient, and green method. Both electron-releasing and withdrawing aldehydes and ketones went smoothly into substituted 2,4,6-triarylpyridines. Notably, the present reaction was carried out in the solvent-fee condition. The key merits of the present protocol are the milder reaction condition, easy workup protocol, high yield of desired pyridines and recyclability and reusability of the catalyst. The developed protocol offers a broad scope of substrate applicability and good sustainability. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have garnered extensive attention as promising candidates for heterogeneous catalysts, attributed to their high surface area and ease of functionalization. In this study, we present a functional imine COF, named Por-NHC-COF, which is meticulously synthesized through a Schiff base reaction between a porphyrin and an N-heterocyclic carbene (NHC) monomer building block. This new COF exhibits good crystallinity and high chemical and thermal stability. Notably, the as-synthesized Por-NHC-COF demonstrates a high catalytic efficiency for organic reactions under gentle conditions. One notable application is its efficacy in Knoevenagel condensation reactions, yielding the target product with exceptional yields (>99%) in a short reaction time (1 hour) at ambient temperature. Remarkably, both the crystallinity and catalytic performance remained unchanged even after 6 recycle tests, indicating the COF's robustness and recyclable nature. Under strong base conditions, the Por-NHC-COF exhibits distinct catalytic performance, due to the successful dehydrogenation of imidazolium into NHC, thereby enabling the catalytic synthesis of γ-butyrolactone at room temperature. The versatile and adaptable nature of our Por-NHC-COF enables it to serve as a potent catalyst for a wide range of chemical transformations. [ABSTRACT FROM AUTHOR]

The presence of refractory micropollutants in natural waters poses significant environmental and health risks. Preferably, advanced oxidation techniques like electro-Fenton (EF) and bio-electro-Fenton (BEF) are used to mitigate micropollutants; nevertheless, their field-scale implementation is limited by prohibitive catalyst cost. As an alternative, waste-iron electrocoagulated algal biomass (A-BC/Fe) was explored as a heterogeneous Fenton catalyst to eliminate dimethyl phthalate (DMP) from wastewater. The Fenton-conducive morphological, chemical, and electrochemical properties of the A-BC/Fe catalyst were revealed by detailed characterisation. In EF treatment, 10 mg/L of DMP was completely degraded within 15 min at pH of 7.0, 50 mM Na2SO4, and cathode potential of − 1.4 V vs. Ag/AgCl. Moreover, the EF system achieved 87.80 ± 2.10% and 96.14 ± 1.10% of DMP removal from secondary and tertiary treated municipal sewage, respectively. The A-BC/Fe catalyst-driven EF process disintegrated DMP into benign non-toxic by-products and showed stable performance over eight batch cycles with only a 1.71% decline in DMP removal efficiency. Further, the A-BC/Fe-catalysed BEF system eliminated 94.81 ± 1.90% of DMP in 4 h while achieving a maximum power density of 124.03 ± 5.64 mW/m2. This investigation underscores the potential of repurposing electrocoagulated algal biomass as a sustainable heterogenous catalyst for micropollutant remediation. [ABSTRACT FROM AUTHOR]

Aromatic hydrocarbons (benzene, toluene, xylene) are valuable intermediates in the chemical and petrochemical industries, so the conversion of butane into aromatics is an important catalytic process from both scientific and industrial viewpoints. In addition to the production of aromatic compounds, the production of hydrogen during aromatization of lower alkanes is also of interest. This review describes industrial processes and presents the main achievements in the field of scientific research into butane aromatization on heterogeneous catalysts over the past 15 years. Current problems and possible directions of studies on the development of catalysts for aromatization of C4 hydrocarbons are also discussed. [ABSTRACT FROM AUTHOR]

An environmentally benign and expeditious protocol was developed for the one‐pot multicomponent synthesis of 4‐aryl‐3‐methylisoxazol‐5(4H)‐ones by the condensation of aldehyde, hydroxyl amine hydrochloride, and ethyl acetoacetate in 50% aq. ethanol at 50 °C. The reaction was catalyzed by magnetically separable carbon microspheres co‐decorated with nanosized iron sulfide and magnetite nanoparticles in 10 wt% amount. The FeS1‐x‐Fe3O4/C nanocatalyst was prepared from iron(III) sulfate loaded iminodiacetate group functionalized styrene‐divinylbenzene based ion exchanger by pyrolysis reaction performed at 600 °C for 4 h. The use of magnetically separable heterogeneous catalyst, aqueous ethanol, short reaction time (30 min), and nonchromatographic purification methods are the striking features of the developed protocol. The isolated yield of the condensation products varied between 81% and 96%. Furthermore, the protocol exhibits high functional group tolerance and includes the use of noncorrosive, nonhazardous reaction conditions affording the product in excellent yields and short reaction time. [ABSTRACT FROM AUTHOR]

Rationally designing distinct acidic and basic sites can greatly enhance performance and deepen our understanding of reaction mechanisms. In our current investigation, we studied the utilization of Brønsted acid sites within layered graphitic carbon nitride (g-C3N4) for the first time to enhance the rate of the Friedländer synthesis. The structural and surface analyses confirm the effective integration of -COOH and -SO3H groups into the g-C3N4 lattice. The surface-functionalized g-C3N4-CO-(CH2)3-SO3H exhibits a remarkable acceleration in quinoline formation, surpassing previously mentioned catalysts, and demonstrating notable recyclability under optimized mild reaction conditions. The heightened reaction rate observed over g-C3N4-CO-(CH2)3-SO3H is attributed to its elevated surface acidity. By probing the Friedländer reaction mechanism through surface characterization, examination of reaction intermediates, and investigation of substrate scope, we elucidate the pivotal role of Brønsted acid sites. This study constitutes a comprehensive exploration of metal-free heterogeneous catalysts for the Friedländer reaction, offering a unique contribution to the field. [ABSTRACT FROM AUTHOR]

Heterogeneous palladium‐based catalysts show excellent catalytic properties for electrocatalytic oxidation of alcohols, but the construction of such heterogeneous catalysts is a challenge. Here, a multiphase tetrahedral PdInMo nanocatalyst is prepared by a one‐pot reaction method. And the multiphase tetrahedral PdInMo nanocatalyst consists of a face‐centered cubic structure and an intermetallic structure. Due to the oxygen affinity of indium and molybdenum atoms, the interface defects of internal multiphase structure, and intermetallic structure, the multiphase concave tetrahedral PdInMo nanocatalyst shows enhanced catalytic efficiency in the electrocatalytic oxidation reaction of methanol and ethanol. Compared with commercial Pd/C catalysts, PdIn0.117Mo0.037 nanocatalyst has the best mass activity and specific activity. In electrocatalysis of methanol oxidation, the mass activity (2205.57 mA mgPd−1) and specific activity (6.67 mA cm−2) are 4.81 and 3.40 times than that of a commercial Pd/C nanocatalyst (458.5 mA mgPd−1, 1.96 mA cm−2), respectively. In the electrocatalysis of ethanol oxidation, the mass activity (2668.49 mA mgPd−1) and specific activity (8.11 mA cm−2) are 4.06 and 3.14 times than that of the commercial Pd/C nanocatalyst (655.83 mA mgPd−1, 2.58 mA cm−2), respectively. This study provides a reference for the design of highly efficient palladium catalysts for alcohol oxidation. [ABSTRACT FROM AUTHOR]

A highly crystalline and robust Zr-hydroxamate metal–organic framework (MOF) was prepared from a pyrazine-based ligand, featuring abundant N,N′ chelating sites. High-degree Pd(II) metalation of the MOF was achieved through straightforward postsynthetic modification, with detailed coordination chemistry elucidated spectroscopically. The Pd-functionalized MOF was then studied as a heterogeneous Suzuki–Miyaura catalyst, through combined experimental/computational methods. [ABSTRACT FROM AUTHOR]

We report the first synthesis of a powdery heterogeneous catalyst using spark ablation technology. A TiO2 powder is aerosolized in a vortex and injected close to the electrode of a spark ablation nanoparticle generator, to be decorated with Ni nanoparticles. The resulting Ni/TiO2 catalyst is readily active in the hydrogenation of CO2 to methane. [ABSTRACT FROM AUTHOR]

Rationally designing distinct acidic and basic sites can greatly enhance performance and deepen our understanding of reaction mechanisms. In our current investigation, we studied the utilization of Brønsted acid sites within layered graphitic carbon nitride (g-C3N4) for the first time to enhance the rate of the Friedländer synthesis. The structural and surface analyses confirm the effective integration of -COOH and -SO3H groups into the g-C3N4 lattice. The surface-functionalized g-C3N4-CO-(CH2)3-SO3H exhibits a remarkable acceleration in quinoline formation, surpassing previously mentioned catalysts, and demonstrating notable recyclability under optimized mild reaction conditions. The heightened reaction rate observed over g-C3N4-CO-(CH2)3-SO3H is attributed to its elevated surface acidity. By probing the Friedländer reaction mechanism through surface characterization, examination of reaction intermediates, and investigation of substrate scope, we elucidate the pivotal role of Brønsted acid sites. This study constitutes a comprehensive exploration of metal-free heterogeneous catalysts for the Friedländer reaction, offering a unique contribution to the field. [ABSTRACT FROM AUTHOR]

Formic acid is considered a promising hydrogen carrier. Biomass‐derived formic acid can be obtained by oxidative decomposition of sugars. This study explored the production of formic acid from cellobiose, a disaccharide consisting of d‐glucose linked by β‐glycosidic bonds using heterogeneous catalysts under mild reaction conditions. The use of alkaline earth metal oxide solid base catalysts like CaO and MgO in the presence of hydrogen peroxide could afford formic acid from cellobiose at 343 K. While CaO gave 14 % yield of formic acid, the oxide itself was converted to a harmful metal peroxide, CaO2 after the reaction. In contrast, MgO could produce formic acid without the formation of the metal peroxide. The difficulty in selectively synthesizing formic acid from cellobiose using these solid base catalysts was due to the poor conversion of cellobiose to glucose. Using a combination of solid acid and base catalysts, a high formic acid yield of 33 % was obtained under mild reaction conditions due to the quantitative hydrolysis of cellobiose to glucose by a solid acid followed by the selective decomposition of glucose to formic acid by a solid base. [ABSTRACT FROM AUTHOR]

Atomically dispersed metal atoms on supports exhibit distinctive advantages in maximizing atomic utilization, which plays an indispensable role in the fabrication of cost‐effective catalysts. In particular, dual‐atom catalysts (DACs) containing dual active sites not only retain the merits of single‐atom catalysts (SACs), but also introduce diverse interactions between the two adjacent metal atoms, endowing them with superior catalytic performance and a broad range of applications. With the development of DACs, it is important to identify active sites and establish intrinsic catalytic mechanisms relationship. The general characterization methods for DACs are comprehensively summarized here, especially the structural nature of dual active sites is discussed in detail. Subsequently, the representative scientific research efforts in various applications including thermocatalysis, electrocatalysis, and photocatalysis are described, with emphasis on structure‐property relationships. Finally, a summary and some prospects for the future of advanced DACs are presented. [ABSTRACT FROM AUTHOR]

The increasing anthropogenic carbon dioxide emissions (CO2) have a huge environmental impact, and CO2 emission reduction is already a common view in our society. Recently, selective hydrogenation of CO2 to methanol has attracted much attention because the process can effectively mitigate CO2 emissions and simultaneously produce high‐value‐added chemicals and fuels. The catalysts play a very important role in achieving high efficiency of CO2 to methanol. As one promising alternative, the alloy catalysts have demonstrated high performance in CO2 hydrogenation to methanol due to their unique geometry and electronic properties. Herein, we review the recent advances in alloy catalysts, including solid solution alloys and intermetallic compounds (mainly Cu‐based, In‐based, Ga‐based, and other alloy catalysts) for heterogeneous catalysis of CO2 hydrogenation to methanol. Moreover, the research ideas and development prospects of alloy catalysts for CO2 hydrogenation to methanol are overviewed to provide the ideas and references for the subsequent research on alloy catalysts for CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

Selective hydrogenation of carboxylic acids to alcohols is generally difficult due to the low reactivity of the carboxy group, and the development of effective catalysts enabling high yields of the target alcohols at low reaction temperatures (<473 K) is challenging. Herein, we found that SiO2‐supported FeOx‐modified Ru (Ru−FeOx/SiO2) with the Fe/Ru molar ratio of 0.4 was an effective and reusable heterogeneous catalyst for the hydrogenation of carboxylic acids at a low reaction temperature of 413 K, providing the alcohols in high yields (up to 97 %). The addition of Fe species drastically suppressed the hydrogenolysis of the C−C bond of the alkyl chain to methane, leading to high selectivity to the alcohols. Based on the activity tests and catalyst characterizations, Ru metals were covered by the reduced Fe species, such as Fe metal or Fe2+, and the active site is the interface between the Fe species and Ru metals. From the reactivity comparison of the related compounds, the alcohol is synthesized via the formation of the aldehyde, and the reactivity of the alcohol is very low in the presence of carboxylic acids. As a result, the hydrogenolysis of the produced alcohol is suppressed, leading to the high selectivity of the alcohol. [ABSTRACT FROM AUTHOR]

Immobilization of the reactive metal sites over high surface area porous nanomaterial is a very demanding route in designing novel nanocatalysts for the synthesis of valuable fine chemicals. Here we report an efficient, eco‐friendly and sustainable route for the synthesis of aminophenoxazinone derivatives via oxidative coupling of o‐aminophenols catalysed by a novel mesoporous highly ordered Ni(II)‐complex functionalized mesoporous heterogeneous organosilica catalyst. A novel structurally characterized Ni(II)‐complex derived from 2‐(I‐(2‐(piperizin‐1‐yl) ethylimino) methyl)‐5‐methylphenol ligand has been immobilised over a 2D‐hexagonally ordered functionalized mesoporous SBA‐15 synthesized via surface functionalization of SBA‐15 material with 3‐aminopropyltriethoxysilane (APTES) to obtain the Ni(II)‐nanocatalyst SANI. Its catalytic activity has been explored for three different substrates like o‐aminophenol (OAP), 3‐amino‐4‐hydroxybenzoic acid (CAP) and 2‐amino‐4‐methylphenol (MAP) that produces corresponding phenoxazinone derivatives having the yields of 92, 81 and 85 %, respectively. suggesting wide scope of this supported mesoporous nanocatalyst. [ABSTRACT FROM AUTHOR]

In this study, a Ni‐based metal‐organic framework (MOF), Ni‐MOF, was synthesized from a mixture of Ni(OAc)2 ⋅ 4H2O, a dicarboxylate, 4,4'‐(1,3,4‐oxadiazole‐2,5‐diyl)dibenzoate (oxdz2−), and a bis(tridentate) ligand, (N,N',N",N"'‐tetrakis(2‐pyridylmethyl)‐1,4‐diaminoxylylene) (tpxn), under ambient conditions using greener solvents in 12 h. The framework was well‐characterized using several analytical techniques. The highly crystalline Ni‐MOF exhibited remarkable polarizing traits with significant uptake of CO2 and water vapor up to 10.53 cm3 g−1 and 290 cm3 g−1, respectively, at 298 K. The isosteric heat of adsorption between Ni‐MOF and CO2 at zero loading was calculated to be 32.43 kJ mol−1. Furthermore, utilizing its CO2‐philic and catalytic features, Ni‐MOF was employed as an excellent heterogeneous catalyst (2.5 mol%) along with very low concentration of TBAB (0.02 mmol) as a co‐catalyst for the synthesis of oxazolidinones via a standard three‐component reaction among an epoxide, a substituted aniline, and carbon dioxide under solvent‐free conditions. A wide range of oxazolidinones including three bioactive derivatives was synthesized using both diverse epoxides and aniline derivatives to demonstrate the substrate scope. The catalyst was proved to be recyclable, reusable, and stable for multiple cycles, without leaching of the metal from it. The mechanistic insights revealed that Ni‐MOF polarizes all three reactants to catalyze the oxazolidinone formation. [ABSTRACT FROM AUTHOR]

ABSTRACT A3 coupling reaction is a multicomponent reaction (MCR) involving aryl aldehydes, phenyl acetylenes and amines to synthesize a variety of biologically active propargylamine derivatives. Herein, we report the preparation of cube‐shaped CuFe2O4 nanoparticles (NPs) via the hydrothermal method in the presence of Lantana camara flower (LCF) extract to use them as catalysts to synthesize propargylamine derivatives. X‐ray diffraction study confirms the formation of CuFe2O4 NPs with cubic spinel structures. In the presence of LCF extract, cube‐shaped CuFe2O4 NPs are formed predominantly irrespective of the type of alkali used as the hydrolyzing agent. However, a mixture of nearly spherical and cube‐shaped particles has been formed in the absence of additives. The synthesized CuFe2O4 NPs exhibit superparamagnetic behaviour and are magnetically ordered. The synthesized cube‐shaped CuFe2O4 NPs exhibit excellent catalytic activity in the A3 coupling reaction between benzaldehyde, piperidine and phenylacetylene to give propargylamine with a yield of 90% under the optimum conditions. The catalyst is highly stable and magnetically retrievable facilitating reusability for up to five cycles without considerable loss of catalytic activity. The protocol is suitable for the synthesis of a diverse range of propargylamine derivatives with moderate to excellent yield. [ABSTRACT FROM AUTHOR]

Multicomponent catalysts can be designed to synergistically combine reaction intermediates at interfacial active sites, but restructuring makes systematic control and understanding of such dynamics challenging. We here unveil how reducibility and mobility of indium oxide species in Ru‐based catalysts crucially control the direct, selective conversion of CO2 to ethanol. When uncontrolled, reduced indium oxide species occupy the Ru surface, leading to deactivation. With the addition of steam as a mild oxidant and using porous polymer layers to control In mobility, Ru−In2O3 interface sites are stabilized, and ethanol can be produced with superior overall selectivity (70 %, rest CO). Our work highlights how engineering of bifunctional active ensembles enables cooperativity and synergy at tailored interfaces, which unlocks unprecedented performance in heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Two novel rare earth-substituted tungstoantimonates [H2N(CH3)2]8Na12[Dy2(H2O)6(tar)(Sb2W21O72)]2·40H2O (DySbW) and [H2N(CH3)2]6Na14[Ho2(H2O)6(tar)(Sb2W21O72)]2·25H2O (HoSbW) (H4tar = tartaric acid) were synthesized. The meso-polyanions are alternately linked by {Na3(H2O)3} clusters and DL-tar ligands to form 1D chains. Notably, HoSbW exhibits excellent catalytic activity and high stability for the synthesis of isoindolinones using EtOH as a green solvent. [ABSTRACT FROM AUTHOR]

The use of supported metal-based heterogeneous catalysts is very ubiquitous in the modern chemical industry. Although high reactivity has been achieved, conventional supported metal-based heterogeneous catalysts commonly face the problem of rapid deactivation, generally involving leaching, poisoning or sintering of the active metal species, which is particularly serious in various solid acid catalysis processes. To overcome these drawbacks, different strategies have been adopted, including strengthening metal–support interactions, confining metal species in various porous materials, or coating the active metal nanoparticles with thin shells, which may generate effective metal-based nanocomposite catalysts with enhanced stability. In this feature article, we summarize our recent work on the design of some metal-based nanocomposites possessing yolk–shell, core–shell or other confined structures for enhanced catalytic applications in several important acid catalysis reactions, such as cycloaddition of CO2, epoxidation of olefins, acylation of aromatic compounds, and transesterification/carbonylation synthesis of organic carbonates. More attention is paid to the design and preparation strategy of metal-based nanocomposite catalysts, which can generate unique catalytically active and stable metal sites for meeting the tough requirements of a specific catalytic reaction. Finally, the existing challenges and the future directions for metal-based nanocomposite catalysts with respect to the preparation strategies and catalytic application prospects are proposed. [ABSTRACT FROM AUTHOR]

There is a significant amount of research being conducted in the field of nitrogen-containing heterocycles due to their diverse applications in different industries. Benzimidazole is one of the heterocyclic compounds formed by connecting the benzene and imidazole rings and shows diverse biological activities. Benzimidazole is also an essential compound in agriculture and industry. In this research, the NiFe2O4@SiO2-Pr-S-nBu-SO3H nanocomposite was prepared and used as a heterogeneous catalyst for synthesizing the 2-aryl benzimidazole derivatives. This protocol involved the reaction between orthophenylene diamine and aromatic aldehydes, with iodine as an oxidizing agent. The prepared catalyst was thoroughly examined using various methods, including infrared Fourier transform spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), and energy dispersive X-ray (EDX) spectroscopy. This protocol offers several advantages such as a short reaction time at room temperature, simple workup, high product yields, simple purification, availability of raw materials, and a catalyst that is both reusable and environmentally friendly. Finally, to characterize the organic compounds, the melting point, FT-IR, and 1H NMR analyses were utilized. [ABSTRACT FROM AUTHOR]

Integrated carbon capture and utilization (ICCU) simplifies the CO2 utilization process by converting chemically combined CO2 molecules into value-added chemicals, leading to a strong energy-saving effect by omitting the CO2 separation process. Two reaction routes for the hydrogenation of amine captured CO2 to methanol over heterogeneous catalysts were summarized: alcoholic hydroxyl groups-promoted CO2 hydrogenation process over Cu or Pd-based catalysts via formate and ester route, and methanol production from the direct hydrogenation of formate over Au-based catalyst. The technical effectiveness of concurrent carbon capture with heterogeneous catalysis toward methanol via alcoholic hydroxyl groups-promoted CO2 hydrogenation is similar to that of the gas-phase CO2 hydrogenation to methanol over heterogeneous catalysts. The sintering of the catalysts, the phase change of the supports, the combination of amines and the catalysts (namely leaching), and the reaction of water with the supports can cause a decrease in the performance of the catalysts. Thus, it is important to rationally design next-generation stable catalysts to achieve amine captured CO2 hydrogenation to methanol while at the same time regenerating amines. The development of heterogeneous catalysts for methanol synthesis in the liquid phase and the development of the CO2 capture process for subsequent conversion(1 ~ 70%) were carefully reviewed. The integration and optimization of multi-pollutant efficient removal technology, selectively coupled CO2 capture technology, and selective routes for methanol synthesis can achieve industrial verification in typical power plants, which is of great significance in promoting energy conservation, emission reduction, and low-carbon footprint. [ABSTRACT FROM AUTHOR]

Biodiesel (methyl esters) has been produced using numerous catalysts to enhance its quality and related productivity. Generally, the raw materials for biodiesel production and its catalysts significantly impact the produced biodiesel's quality. In addition, the heterogeneous catalysts are promising as catalysts in the transesterification for biodiesel production and can be used continuously during this production. In particular, these catalysts are essential for green biodiesel production because of their high activity, thermal stability, and reusability. Hence, several homogeneous and heterogeneous (acidic and alkaline) catalysts for biodiesel production, particularly the naturally derived heterogeneous catalysts, are reviewed in this article. Further, the different heterogeneous catalysts for biodiesel production have been studied extensively as replacements for the respective homogeneous catalyst. Specifically, this replacement is aimed at the simultaneous esterification and transesterification of the nonedible and low-cost biomasses under moderate conditions producing biodiesel. Moreover, this study analyzes biodiesel's impact and long-term performance in various applications. Finally, it also reports the advancements in biodiesel production in terms of the catalysts used in it and its processes to aid further developments in biodiesel production. [ABSTRACT FROM AUTHOR]

The present work described the one-pot multicomponent green and novel protocol for the synthesis of dihydrothiazolo [3,2-a] purine-2(1H)-one derivatives from novel purines and substituted 2-amino-thiazoles using BEC (pH 12.5, 10% by weight) as a recyclable heterogeneous catalyst in environmentally sustainable reaction medium PEG-400. The antibacterial potency was studied using a disc diffusion assay against two bacterial strains such as Staphylococci aureus (MTCC 1430) and Escherichia coli (MTCC 1573). The results of biological tests of newly synthesized derivatives 4a, 4b, 4d, 4g, and 4h display marked antibacterial potency against tested pathogens. The biological relevance of these synthesized derivatives is due to the presence of thiazole nucleus in combination with a purine ring. Further, structure conformation of synthesized titled compounds was presented with different spectroscopic methods such as 1H-NMR, 13C-NMR, IR, and GCMS. Numerous benefits of the current method include the catalyst's recyclability, clean reaction conditions, a quick reaction rate, increased product yield, and the lack of dangerous reagents. [ABSTRACT FROM AUTHOR]

Zirconium doped cerium nanoparticles have been found to be an excellent heterogeneous catalyst for the one-pot multi-component reactions of Barbituric acid, aromatic aldehyde and malononitrile to yield the Pyrano(2,3-d) pyrimidine derivatives in aqueous media. The results showed that nanosized CeO2 − ZrO2 has a potential catalytic material for the synthesis of title compound. All the synthesized molecules were determined and characterised by chromatographic and spectroscopic (IR,1H-NMR, 13C-NMR, HR-MS) analysis. The formation, size and morphology of the metal ions present in the material is confirmed by powdered X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The synthesised compounds have shown good to excellent cytotoxicity against human breast cancer cell line MDA-MB-453. [ABSTRACT FROM AUTHOR]

Strong metal‐support interaction (SMSI) has drawn much attention in heterogeneous catalysts due to its stable and excellent catalytic efficiency. However, construction of high‐performance oxide‐capsulated metal nanostructures meets great challenge in materials thermodynamic compatibility. In this work, dynamically controlled formation of oxide‐capsulated metal nanoparticles (NPs) structures is demonstrated by ultrafast laser plasmonic nanowelding. Under the strong localized electromagnetic field interaction, metal (Au) NPs are dragged by an optical force toward oxide NPs (TiO2). Intense energy is simultaneously injected into this heterojunction area, where TiO2 is precisely ablated. With the embedding of metal into oxide, optical force on Au gradually turned from attractive to repulsive due to the varied metal‐dielectric environment. Meanwhile, local ablated oxides are redeposited on Au NP. Upon the whole coverage of metal NP, the implantation behavior of metal NP is stopped, resulting in a controlled metal‐oxide eccentric structure with capsulated oxide layer thickness ≈0.72–1.30 nm. These oxide‐capsulated metal NPs structures can preserve their configurations even after thermal annealing in air at 600 °C for 10 min. This ultrafast laser plasmonic nanowelding can also extend to oxide‐capsulated metal nanostructure fabrication with broad materials combinations (e.g., Au/ZnO, Au/MgO, etc.), which shows great potential in designing/constructing nanoscale high‐performance catalysts. [ABSTRACT FROM AUTHOR]

The growth of the environment depends upon developing greener and ecological methods for managing pollutants and contamination from industrial wastewater, which causes significant effects on human health. The removal of these pollutants from wastewater using nanomaterials covers an ecological method that is free from expensive and secondary pollution. In this report, we developed magnetic iron nanoparticles from Chenopodium glaucum (CG), which showed excellent adsorption capacity at pH 5 for selective Hg2+ and Pb2+ metal ions among various heavy metal ions, with maximum adsorption capacities of 96.9 and 94.1%, respectively. These metals' adsorption process conforms to the Langmuir model, which suggests that monolayer adsorption transpires on CG–Fe2O3 nanoparticles. CG–Fe2O3 nanoparticles also act as an efficient and recyclable heterogeneous catalyst for one-pot synthesis of xanthene derivatives, yielding products with high yields (up to 97%) and excellent purity (crystalline form) within a short timeframe (6 min) using microwave irradiations (at 120 W). [ABSTRACT FROM AUTHOR]