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Chemistry, a vital tool for sustainable development, faces a challenge due to the lack of clear guidance on actionable steps, hindering the optimal adoption of sustainability practices across its diverse facets from discovery to implementation. This Scientific Perspective explores established frameworks and principles, proposing a conciliated set of triple E priorities anchored on Environmental, Economic, and Equity pillars for research and decision making. We outline associated metrics, crucial for quantifying impacts, classifying them according to their focus areas and scales tackled. Emphasizing catalysis as a key driver of sustainable synthesis of chemicals and materials, we exemplify how triple E priorities can practically guide the development and implementation of processes from renewables conversions to complex customized products. We summarize by proposing a roadmap for the community aimed at raising awareness, fostering academia–industry collaboration, and stimulating further advances in sustainable chemical technologies across their broad scope. [ABSTRACT FROM AUTHOR]

Single‐atom heterogeneous catalysts (SACs) hold promise as sustainable alternatives to metal complexes in organic transformations. However, their working structure and dynamics remain poorly understood, hindering advances in their design. Exploiting the unique features of droplet‐based microfluidics, we present the first in‐situ assessment of a palladium SAC based on exfoliated carbon nitride in Suzuki–Miyaura cross‐coupling using X‐ray absorption spectroscopy. Our results confirm a surface‐catalyzed mechanism, revealing the distinct electronic structure of active Pd centers compared to homogeneous systems, and providing insights into the stabilizing role of ligands and bases. This study establishes a valuable framework for advancing mechanistic understanding of organic syntheses catalyzed by SACs. [ABSTRACT FROM AUTHOR]

C1 coupling reactions over zeolite catalysts are central to sustainable chemical production strategies. However, questions persist regarding the involvement of CO in ketene formation, and the impact of this elusive oxygenate intermediate on reactivity patterns. Using operando photoelectron photoion coincidence spectroscopy (PEPICO), we investigate the role of CO in methyl chloride conversion to hydrocarbons (MCTH), a prospective process for methane valorization with a reaction network akin to methanol to hydrocarbons (MTH) but without oxygenate intermediates. Our findings reveal the transformative role of CO in MCTH at the low pressures, inducing ketene formation in MCTH and boosting olefin production, confirming the Koch carbonylation step in the initial stages of C1 coupling. We uncover pressure‐dependent product distributions driven by CO‐induced ketene formation, and its subsequent desorption from the zeolite surface, which is enhanced at low pressure. Inspired by the above results, extension of the co‐feeding approach to CH3OH as another simple oxygenate showcases the additional potential for improved catalyst stability in MCTH at ambient pressure. [ABSTRACT FROM AUTHOR]

Catalytic hydrogenolysis has the potential to convert high‐density polyethylene (HDPE), which comprises about 30 % of plastic waste, into valuable alkanes. Most investigations have focused on increasing activity for lab grade HDPEs displaying low molecular weight, with limited mechanistic understanding of the product distribution. No efficient catalyst is available for consumer grades due to their lower reactivity. This study targets HDPE used in bottle caps, a waste form generated globally at a rate of approximately one million units per hour. Ultrafine ruthenium particles (1 nm) supported on titania (anatase) achieved up to 80 % conversion into light alkanes (C1−C45) under mild conditions (498 K, 20 bar H2, 4 h) and were reused for three cycles. Small ruthenium nanoparticles were critical to achieving relevant conversions, as activity sharply decreased with particle size. Selectivity commonalities and peculiarities across HDPE grades were disclosed by a reaction modelling approach applied to products. Isomerization cedes to backbone scission as the reaction progresses. Within this trend, low molecular weight favor isomerization whilst high molecular weight favor cleavage. Commercial caps obeyed this trend with decreased activity, anticipating the influence of additives in realistic processing. This study demonstrates effective hydrogenolysis of consumer grade polyethylene and provides selectivity patterns for product control. [ABSTRACT FROM AUTHOR]

Artificial leaves (a‐leaves) can reduce carbon dioxide into syngas using solar power and could be combined with thermo‐ and biocatalytic technologies to decentralize the production of valuable products. By providing variable CO : H2 ratios on demand, a‐leaves could facilitate optimal combinations and control the distribution of products in most of these hybrid systems. However, the current design procedures of a‐leaves concentrate on achieving high performance for a predetermined syngas composition. This study demonstrates that incorporating the electrolyte flow as a design variable enables flexible production without compromising performance. The concept was tested on an a‐leaf using a commercial cell, a Cu2O:Inx cathodic catalyst, and an inexpensive amorphous silicon thin‐film photovoltaic module. Syngas with CO : H2 ratio in the range of 1.8–2.3 could be attained with only 2 % deviation from the optimal cell voltage and controllable solely by catholyte flow. These features could be beneficial for downstream technologies such as Fischer‐Tropsch synthesis and anaerobic fermentation. [ABSTRACT FROM AUTHOR]

Ternary Pd‐In2O3/ZrO2 catalysts exhibit technological potential for CO2‐based methanol synthesis, but developing scalable systems and comprehending complex dynamic behaviors of the active phase, promoter, and carrier are key for achieving high productivity. Here, we show that the structure of Pd‐In2O3/ZrO2 systems prepared by wet impregnation evolves under CO2 hydrogenation conditions into a selective and stable architecture, independent of the order of addition of Pd and In phases on the zirconia carrier. Detailed operando characterization and simulations reveal a rapid restructuring driven by the metal‐metal oxide interaction energetics. The proximity of InPdx alloy particles decorated by InOx layers in the resulting architecture prevents performance losses associated with Pd sintering. The findings highlight the crucial role of reaction‐induced restructuring in complex CO2 hydrogenation catalysts and offer insights into the optimal integration of acid‐base and redox functions for practical implementation. [ABSTRACT FROM AUTHOR]

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Mixed zinc‐zirconium oxides, ZnZrOx, are highly selective and stable catalysts for CO2 hydrogenation to methanol, a pivotal energy vector. However, their activity remains moderate, and descriptors to design improved systems are lacking. This work applies flame spray pyrolysis (FSP), a one‐step and scalable method, to synthesize a series of ZnZrOx catalysts, and systematically compares them to coprecipitated (CP) analogs to establish deeper synthesis–structure–performance relationships. FSP systems (up to 5 mol%) generally display a threefold higher methanol productivity compared to their CP counterparts. In‐depth characterization and theoretical simulations show that, unlike CP, FSP maximizes the surface area and formation of atomically dispersed Zn2+ sites incorporated in lattice positions within the ZrO2 surface, which is key to improving performance. Analysis by in situ electron paramagnetic resonance (EPR) spectroscopy reveals that the specific architecture of the flame‐made catalyst markedly fosters the generation of oxygen vacancies. Together with surrounding Zn and Zr‐O atoms, the oxygen vacancies create active ensembles that favor methanol formation through the formate path while suppressing undesired CO production, as confirmed by kinetic modeling. This study elucidates the nature of active sites and their working mechanism, pushing forward ZnZrOx‐catalyzed methanol synthesis by providing a new benchmark for this cost‐effective and earth‐abundant catalyst family. [ABSTRACT FROM AUTHOR]

Bimetallic single–atom catalysts (b–SACs) have recently gained prominence by virtue of the unique catalytic cooperative interactions they can exhibit, intertwining electronic and geometric effects. To date, research efforts have exclusively focused on direct mechanisms such as electron density transfer or sequential reactivity. Herein, the first study on indirect, coordination–induced catalytic synergies in carbon‐supported RuPt SACs is conducted. To this end, a holistic approach is developed, combining i) precision synthesis, ii) advanced characterization, iii) exploration of single–site adsorption properties via the hydrogen evolution reaction, and iv) modeling through density functional theory. Despite the lack of both intermetallic coordination in the first or second shell and charge redistribution effects, the RuPt SACs exhibit a H2 formation rate enhanced up to 15–fold compared with their monometallic counterparts. To unfold the origin of the intermetallic cooperativity, modifications of the structural and catalytic properties induced by the integration of a second metal species are investigated. Thus, Pt atoms are found to selectively occupy the most energeticallyfavorable cavities in the support, prompting Ru atoms to assume a distinct, more active, configuration. This contribution unveils a novel principle of bimetallic cooperativity, demonstrating the key role of integrative experimental and computational analyses in studying b–SACs. [ABSTRACT FROM AUTHOR]

Solar‐driven transfer hydrogenation of unsaturated bonds has received considerable attention in the research area of sustainable organic synthesis; however, water, the ultimate green source of hydrogen, has rarely been investigated due to the high barrier associated with splitting of water molecules. We report a carbon‐nitride‐supported palladium single‐atom heterogeneous catalyst with unparalleled performance in photocatalytic water‐donating transfer hydrogenation compared to its nanoparticle counterparts. Isotopic‐labeling experiments and operando nuclear magnetic resonance measurements confirm the direct hydrogenation mechanism using in situ‐generated protons from water splitting under visible‐light irradiation. Density functional theory calculations attribute the high activity to lower barriers for hydrogenation, facilitated desorption of ethylbenzene, and facile hydrogen replenishment from water on the atomic palladium sites. [ABSTRACT FROM AUTHOR]

Chemistry is vital for society , but its practices must align with sustainable development. While attention often focuses on individual pillars—environment, economy, or equity—true sustainability requires alignment across all three. The cover image depicts a sustainability compass, symbolizing the integration of diverse principles into a unified set of triple E priorities proposed by Javier Pérez‐Ramírez et al. in their Scientific Perspective (e202318676) to guide efforts in the chemical sciences...By Sharon Mitchell; Antonio J. Martín; Gonzalo Guillén‐Gosálbez and Javier Pérez‐RamírezReported by Author; Author; Author; Author [Extracted from the article]

Chemistry is vital for society , but its practices must align with sustainable development. While attention often focuses on individual pillars—environment, economy, or equity—true sustainability requires alignment across all three. The cover image depicts a sustainability compass, symbolizing the integration of diverse principles into a unified set of triple E priorities proposed by Javier Pérez‐Ramírez et al. in their Scientific Perspective (e202318676) to guide efforts in the chemical sciences...By Sharon Mitchell; Antonio J. Martín; Gonzalo Guillén‐Gosálbez and Javier Pérez‐RamírezReported by Author; Author; Author; Author [Extracted from the article]

The production of nitrous oxide, N2O, via NH3 oxidation is not on a practical scale due to the lack of a suitable catalyst. Instead, it is produced via thermal decomposition of NH4NO3, rendering N2O too costly and limiting its prospective uses. Herein, we report CeO2‐supported Au nanoparticles (2–3 nm) as a highly selective catalyst for low‐temperature NH3 oxidation to N2O, exhibiting two orders of magnitude higher space–time yield than the state‐of‐the‐art Mn−Bi/α‐Al2O3 and remarkable stability over 70 h on stream. The reaction proceeds via a Mars–van Krevelen mechanism, with the density of interfacial Auδ+ species and the oxygen storage capacity of CeO2 identified as the key performance descriptors. The latter could be enhanced by cobalt doping, improving the catalytic activity and setting a new benchmark for N2O productivity. These findings establish NH3 oxidation as an efficient process for N2O manufacture and facilitate its broader utilization in selective oxidations. [ABSTRACT FROM AUTHOR]

A plethora of metal promoters have been applied to enhance the performance of In2O3 in CO2 hydrogenation to methanol, a prospective energy carrier. However, the lack of systematic catalyst preparation and evaluation precludes a direct comparison of their speciation and promotional effects, and consequently, the design of an optimal system. Herein, flame spray pyrolysis (FSP) is employed as a standardized synthesis method to introduce nine metal promoters (0.5 wt.%) into In2O3. Methanol productivity generally increased on M‐In2O3 with selectivity following Pd ≈ Pt > Rh ≈ Ru ≈ Ir > Ni ≈ Co > Ag ≈ In2O3 > Au. In‐depth characterization, kinetic analyses, and theoretical calculations reveal a range of metal‐dependent speciation which dictate catalyst architecture and degree of promotion. Atomically‐dispersed promoters (Pd, Pt, Rh, Ru, and Ir) grant the highest improvement in performance, particularly Pd and Pt, which markedly promote hydrogen activation while hindering undesired CO formation. In contrast, metals in clustered (Ni and Co) and nanoparticle (Ag and Au) forms display moderate and no promotion, respectively. This study provides an atomic‐level understanding of In2O3 promotion based on a unified protocol, and highlights the potential of FSP to engineer complex catalytic systems toward more efficient energy transformations. [ABSTRACT FROM AUTHOR]

The article discusses the importance of developing improved in-situ characterization tools for designing heterogeneous catalysts for organic syntheses. The authors present an innovative in-situ X-ray absorption spectroscopy approach using droplet-based microfluidics to study palladium single-atom catalysts in Suzuki-Miyaura coupling. The results demonstrate the feasibility of the technique and its potential to provide new mechanistic insights. Additionally, another research article by different authors explores the discovery of non-Fenton-type reactive oxygen species driving abiotic CH4 production, offering a new approach for engineering CH4 production. [Extracted from the article]

The article titled "Titelbild: Droplet-Based Microfluidics Reveals Insights into Cross-Coupling Mechanisms over Single-Atom Heterogeneous Catalysts" discusses the development of in-situ characterization tools for heterogeneous catalysts in organic syntheses. The authors, Andrew J. deMello, Javier Pérez-Ramírez, Sharon Mitchell, and their colleagues, demonstrate the use of an innovative in-situ X-ray absorption spectroscopy approach using droplet-based microfluidics to study palladium single-atom catalysts in Suzuki-Miyaura coupling. The results of their study highlight the feasibility of this technique and its potential to provide new mechanistic insights. Additionally, the article mentions another research article by Shungui Zhou, Yujie Xiong, and their colleagues, which reports on the discovery of non-Fenton-type reactive oxygen species driving abiotic CH4 production, offering a new approach for engineering CH4 production. [Extracted from the article]

The article titled "Back Cover: Consumer Grade Polyethylene Recycling via Hydrogenolysis on Ultrafine Supported Ruthenium Nanoparticles" discusses the development of catalysts for the chemical recycling of high-density polyethylene. The researchers, led by Javier Pérez-Ramírez, found that 1-nm ruthenium particles supported on titania can effectively catalyze the hydrogenolysis of plastic caps used in soft drinks, converting them into C1-C45 alkanes. The study also examines the impact of common additives on the catalytic process. The authors provide valuable insights into the mechanistic routes and deactivation pathways involved in the recycling process. [Extracted from the article]

The article titled "Consumer Grade Polyethylene Recycling via Hydrogenolysis on Ultrafine Supported Ruthenium Nanoparticles" published in Angewandte Chemie discusses the development of catalysts for the chemical recycling of high-density polyethylene. The researchers, led by Javier Pérez-Ramírez, found that 1-nm ruthenium particles supported on titania can effectively catalyze the hydrogenolysis of plastic caps used in soft drinks, converting them into C1-C45 alkanes. The study also examines the impact of common additives on the catalytic process. The authors of the article are Shibashish D. Jaydev, Antonio J. Martín, Marc-Eduard Usteri, Katia Chikri, Henrik Eliasson, Rolf Erni, and Javier Pérez-Ramírez. [Extracted from the article]

Catalysts based on individual precious metals on carbon‐ and oxide‐based carriers have shown remarkably selective behavior in the hydrodebromination of CH2Br2 to CH3Br, an important transformation within halogen‐mediated methane upgrading processes. However, the high susceptibility of the active phase to coking and to sintering, which cannot be overcome by controlling the nuclearity of the metal species, hinders their practical implementation. Herein, a platform of carbon‐supported Ir−Ru catalysts with distinct metal ratios at comparable metal nanoparticle size (ca. 1.0 nm) was adopted to systematically study the effects of a second metal on reactivity and stability. Catalytic tests reveal ruthenium‐doped iridium nanoparticles as the first system that combines high CH3Br selectivity (up to 93 %) with unprecedented stability, outperforming any of the previously reported catalysts. This superior performance was rationalized by the intimate interaction between the two metals, forming ruthenium‐poor surface alloys, which enable suppressing deactivation mechanisms as well as over hydrogenation/coking pathways. [ABSTRACT FROM AUTHOR]

Efforts to selectively convert polypropylene (≈30 % of all plastic waste) have not been particularly successful. Typical distributions span from gas to solid products, highlighting a challenging cleavage control. Here, carbon‐supported platinum nanoparticles were designed for complete hydrocracking into liquid hydrocarbons (C5–C45). The metal and carrier phases operated synergistically. The cleavage activity depended on platinum and its rate rose with decreasing particle size. The carbon carrier controlled selectivity via hydrocarbon binding strength, which depended on the chain length and on the surface oxygen concentration. An optimal binding provided by carbons with high oxygen content promoted both adsorption of long chains and desorption of short products. This strategy achieved an unprecedented 80 % selectivity toward motor oil (C21–C45). Carbons exhibiting too strong binding (low oxygen content) hindered product desorption, while non‐binding materials (e. g., silica or alumina) did not promote plastic–Pt contact, leading in both cases to low performance. This work pioneers design guidelines in a key process towards a sustainable plastic economy. [ABSTRACT FROM AUTHOR]

The use of ethane as a platform molecule for the manufacture of polyvinyl chloride (PVC) is a longstanding challenge, which would allow to reduce the raw material costs and CO2 emissions to produce this plastic. Herein, we discover that rare earth oxychlorides catalyze in a selective (up to 90 %) and stable (>50 h on stream) manner the reaction of ethane and molecular chlorine into 1,2‐dichloroethane, which, upon established cracking, will translate into an order of magnitude higher vinyl chloride productivity compared to ethane oxychlorination technologies. In addition, representative europium oxychloride was supported on suitable carriers and was demonstrated to be selective (up to 90 %) and stable (>40 h on stream) in extrudate form. These findings bring the ethane‐based production of PVC one step closer to implementation. [ABSTRACT FROM AUTHOR]

Nanostructuring earth‐abundant metals as single atoms or clusters of controlled size on suitable carriers opens new routes to develop high‐performing heterogeneous catalysts, but resolving speciation trends remains challenging. Here, we investigate the potential of low‐nuclearity iron catalysts in the continuous liquid‐phase semi‐hydrogenation of various alkynes. The activity depends on multiple factors, including the nuclearity and ligand sphere of the metal precursor and their evolution upon interaction with the mesoporous graphitic carbon nitride scaffold. Density functional theory predicts the favorable adsorption of the metal precursors on the scaffold without altering the nuclearity and preserving some ligands. Contrary to previous observations for palladium catalysts, single atoms of iron exhibit higher activity than larger clusters. Atomistic simulations suggest a central role of residual carbonyl species in permitting low‐energy paths over these isolated metal centers. [ABSTRACT FROM AUTHOR]

The impact of carbon monoxide on CO2‐to‐methanol catalysts has been scarcely investigated, although CO will comprise up to half of the carbon feedstock, depending on the origin of CO2 and process configuration. In this study, copper‐based systems and ZnO−ZrO2 are assessed in cycling experiments with hybrid CO2−CO feeds and their CO sensitivity is compared to In2O3‐based materials. All catalysts are found to be promoted upon CO addition. Copper‐based systems are intrinsically more active in CO hydrogenation and profit from exploiting this carbon source for methanol production, whereas CO induces surplus formation of oxygen vacancies (i. e. the catalytic sites) on ZnO−ZrO2, as in In2O3‐based systems. Mild‐to‐moderate deactivation occurs upon re‐exposure to CO2‐rich streams, owing to water‐induced sintering for all catalysts except ZnO−ZrO2, which responds reversibly to feed variations, likely owing to its more hydrophobic nature and the atomic mixing of its metal components. Catalytic systems are categorized for operation in hybrid CO2−CO feeds, emphasizing the significance of catalyst and process design to foster advances in CO2 utilization technologies. [ABSTRACT FROM AUTHOR]

Metal‐free carbon catalysts represent attractive alternatives to platinum and chromium‐containing systems for the on‐purpose production of propylene, a crucial chemical building block, via non‐oxidative propane dehydrogenation. However, the role of heteroatoms in determining reactivity and stability is poorly understood. Here, the study of a platform of polyaniline‐derived and activated carbons, with distinct porous properties, and heteroatom type, content, and speciation, enables establishing improved structure‐performance relationships. In‐depth characterization reveals that, while several oxygen species potentially catalyze the reaction, carbonyl groups are the main functionality governing the activity. Oxygen loss via propane‐driven water evolution is the main deactivation path. Six‐fold enhanced stability evidenced over carbon catalysts derived from KOH‐post‐treated polyanilines demonstrates the importance of controlling the nanostructure for enhancing longevity. [ABSTRACT FROM AUTHOR]

A myriad of heterogeneous catalysts comprises multiple phases that need to be precisely structured to exert their maximal contribution to performance through electronic and structural interactions at their peripheries. In view of the nanometric, tridimensional, and anisotropic nature of these materials, a quantification of the interface and the impact of catalytic sites located there on the global performance is a highly challenging task. Consequently, the true origin of catalysis often remains subject of debate even for widely studied materials. Herein, an integrated strategy based on microfabricated catalysts and a custom‐designed reactor is introduced for determining interfacial contributions upon catalytic activity assessment under process‐relevant conditions, which can be easily implemented in the common catalysis research infrastructure and will accelerate the rational design of multicomponent heterogeneous catalysts for diverse applications. The method is validated by studying the high‐pressure continuous‐flow hydrogenation of CO and CO2 over Cu–ZnO catalysts, revealing linear correlations between the methanol formation rate and the interface between the metal and the oxide. Characterization of fresh and used materials points to the model catalyst preparation as the current challenge of the methodology that can be addressed through further development of nanotechnological tools. [ABSTRACT FROM AUTHOR]

Developing efficient solid catalysts is necessary when for example moving from batch chemistry to continuous flow systems. In this work, scale‐up effects of zeolite‐based catalyst materials have been tested in aldol condensation as a model reaction for bio‐oil upgrading via deoxygenation. For this purpose, shaped catalyst bodies were obtained via extrusion of ultrastable Y zeolite (USY) using either attapulgite (Att.) or bentonite (Bent.) as clay binder, followed by post‐alkali metal ion grafting of K+ after (rather than before) extrusion. This approach proved essential to preserve the catalysts' crystallinity. The Att.‐bound catalyst body was more active than its Bent.‐counterpart, correlating well with the observed changes in physicochemical properties. The K‐(USY/Att.) catalyst showed new basic oxygen and strong Lewis acidic sites resulting from clay incorporation, in addition to the Lewis acid (K+) and basic sites (K−OH) created upon grafting. For K‐(USY/Bent.), the grafting proved less efficient, likely due to pore blockage caused by the binder. Bent. addition resulted in acid sites of moderate Brønsted and strong Lewis acidity, but hardly any of the basicity desired for the aldol condensation reaction. The poor potassium grafting yet led to some cation exchange with the binder (likely with the Na+ naturally present in the Bent. material). The results obtained demonstrate the critical importance of the choice of the binder material and the synthesis protocol adopted for upscaling solid base materials in the form of catalyst bodies. [ABSTRACT FROM AUTHOR]

Identification and quantification of redox‐active centers at relevant conditions for catalysis is pivotal to understand reaction mechanisms and requires development of advanced operando methods. Herein, we demonstrate operando EPR spectroscopy as an important technique to quantify the oxidation state of representative CrPO4 and EuOCl catalysts during propane oxychlorination, an attractive route for propylene production. In particular, we show that the space‐time‐yield of C3H6 correlates with the amount of Cr2+ and Eu2+ ions generated over the catalysts during reaction. These results provide a powerful strategy to gather quantitative understanding of selective alkane oxidation, which could potentially be extrapolated to other functionalization approaches and operating conditions. [ABSTRACT FROM AUTHOR]

Decarbonizing the chemical industry will eventually entail using CO2 as a feedstock for chemical synthesis. However, many chemical syntheses involve CO2 reduction using inputs such as renewable hydrogen. In this review, chemical processes are discussed that use CO2 as an oxidant for upgrading hydrocarbon feedstocks. The captured CO2 is inherently reduced by the hydrocarbon co‐reactants without consuming molecular hydrogen or renewable electricity. This CO2 utilization approach can be potentially applied to synthesize eight emission‐intensive molecules, including olefins and epoxides. Catalytic systems and reactor concepts are discussed that can overcome practical challenges, such as thermodynamic limitations, over‐oxidation, coking, and heat management. Under the best‐case scenario, these hydrogen‐free CO2 reduction processes have a combined CO2 abatement potential of approximately 1 gigatons per year and avoid the consumption of 1.24 PWh renewable electricity, based on current market demand and supply. [ABSTRACT FROM AUTHOR]

Methanol is an attractive energy vector in a closed loop including its synthesis from CO2 and H2 and on‐demand reforming to the starting feedstocks. Catalytic materials for the two reactions were mostly studied separately, with very few works assessing the feasibility of the same system for both. Here, key kinetic drivers of methanol synthesis (MS) and methanol steam reforming (MSR) were identified for the main catalyst families, with special focus on Cu−ZnO−Al2O3, In2O3, and Pd/ZrO2. It was shown that the relative activity level was preserved in either direction, whereas the distinctly favored (reverse) water‐gas shift modulated selectivity differently. Low selectivity in kinetically controlled MS could be overcome in MSR by exploiting thermodynamics as the driving force, with many catalysts unfit for MS still comprising appealing candidates for MSR and only few being suited for MS as well as MSR. Overall, readily identifiable properties describing catalyst behavior in the forward and backward reactions were highlighted, effectively linking research in the two fields and setting a stronger basis for developing a methanol‐based hydrogen storage unit with a single reactor. [ABSTRACT FROM AUTHOR]

Carbon capture and utilization (CCU) has recently gained broad interest in the chemical industry. Direct electro‐ and thermocatalytic technologies are currently the focus of intense research, where the former employs electricity directly to reduce the CO2 molecule, while the latter comprises hydrogenation of CO2 in tandem with electrocatalytic water splitting. So far, it remains unclear which of the two is superior, yet this information is considered critical. Focusing on the platform chemical ethylene, the two CCU routes were compared using state‐of‐the‐art performances with the fossil technology considering different power and CO2 sources. The thermo‐route was found to be, at present, economically and environmentally better, yet under the same electrolyzer efficiencies, the electro‐route would become superior. CCU routes could substantially improve the carbon footprint of the fossil ethylene (by 236 %) while decreasing at the same time impacts on human health, ecosystem quality, and resources (64, 140, and 80 %, respectively). However, they are economically unattractive even when considering externalities (indirect cost of environmental impacts), that is, 1.7‐ to 3.9‐fold more expensive compared to the current fossil‐based analogue. Acknowledging this limitation, the concept of hybridization was applied as a means to smooth the transition towards more sustainable chemicals. Accordingly, it was found that an optimal hybrid plant could produce carbon‐neutral (cradle‐to‐gate) ethylene with a premium of only 30 % over the current market prices by judiciously combining CCU routes with fossil technologies. [ABSTRACT FROM AUTHOR]

The methoxycarbonylation of anilines stands as an attractive method for the phosgene‐free production of carbamates. Despite the high yields obtained for ceria catalysts, the reduction of the amount of side products and the prevention of catalyst deactivation still represent major hurdles in this chemistry. One advantage of ceria is the possibility of tuning its reactivity by doping its lattice with other metals. In the present work, a series of doped ceria‐based materials, prepared by substitution with metals, are evaluated in the methoxycarbonylation of 2,4‐diaminotoluene with dimethyl carbonate. Among all catalysts, containing Eu, Hf, La, Pr, Sm, Tb, Y or Zr, ceria promoted with 2 mol % Zr exhibited 96 % selectivity towards the desired carbamates, improving the pure CeO2 catalyst. Density functional theory demonstrates that two descriptors are needed: 1) a geometric factor that governs the reduction of energy barriers for carbamate formation through ureas; 2) catalyst basicity as N−H bonds need to be activated. Assessment in subsequent reaction cycles revealed that the CeO2–ZrO2 catalyst is more stable than bulk CeO2, along with the reduction of fouling processes. [ABSTRACT FROM AUTHOR]

The electroreduction of carbon dioxide using renewable electricity is an appealing strategy for the sustainable synthesis of chemicals and fuels. Extensive research has focused on the production of ethylene, ethanol and n‐propanol, but more complex C4 molecules have been scarcely reported. Herein, we report the first direct electroreduction of CO2 to 1‐butanol in alkaline electrolyte on Cu gas diffusion electrodes (Faradaic efficiency=0.056 %, j1‐Butanol=−0.080 mA cm−2 at −0.48 V vs. RHE) and elucidate its formation mechanism. Electrolysis of possible molecular intermediates, coupled with density functional theory, led us to propose that CO2 first electroreduces to acetaldehyde‐a key C2 intermediate to 1‐butanol. Acetaldehyde then undergoes a base‐catalyzed aldol condensation to give crotonaldehyde via electrochemical promotion by the catalyst surface. Crotonaldehyde is subsequently electroreduced to butanal, and then to 1‐butanol. In a broad context, our results point to the relevance of coupling chemical and electrochemical processes for the synthesis of higher molecular weight products from CO2. [ABSTRACT FROM AUTHOR]

Chemical modifiers enhance the efficiency of metal catalysts in numerous applications, but their introduction often involves toxic or expensive precursors and complicates the synthesis. Here, we show that a porous boron nitride carrier can directly modify supported palladium nanoparticles, originating unparalleled performance in the continuous semi‐hydrogenation of alkynes. Analysis of the impact of various structural parameters reveals that using a defective high surface area boron nitride and ensuring a palladium particle size of 4–5 nm is critical for maximizing the specific rate. The combined experimental and theoretical analyses point towards boron incorporation from defects in the support to the palladium subsurface, creating the desired isolated ensembles determining the selectivity. This practical approach highlights the unexplored potential of using tailored carriers for catalyst design. [ABSTRACT FROM AUTHOR]

Catalytic alkane oxychlorination has recently been demonstrated as attractive for the selective conversion of natural gas into olefins, which are pivotal commodities of the chemical industry. Herein, the oxychlorination of ethane, propane, and butane over metal phosphates (Fe, Mn, and V), europium oxychloride, titanium oxide, and cerium oxide is investigated to assess the role of the carbon number on the reactivity and product distribution. Three categories of catalysts are distinguished: systems showing the highest activity in the oxychlorination of ethane CeO2, (VO)2P2O7, propane (EuOCl, FePO4, TiO2), or butane (Mn3(PO4)2). All catalysts achieve high (70–95%) selectivity toward ethylene in ethane oxychlorination, whereas they favor combustion and cracking pathways in the case of propane and particularly of butane. Furthermore, the catalytic oxidation of alkane and of HCl and alkyl chloride dehydrochlorination is assessed to rationalize the catalytic performance, revealing a linear correlation between the reactivity of the catalysts and the ability of the material to evolve chlorine, which weakens with increasing carbon number. In addition, the olefin selectivity in alkane oxychlorination is found to be driven by the rate of alkyl chloride dehydrochlorination and the propensity toward alkane cracking and combustion over the catalysts, both increasing from ethane to butane. [ABSTRACT FROM AUTHOR]

Converting syngas obtained from renewable or abundant feedstocks into higher alcohols (HA) is a potentially more sustainable route to these important chemicals and fuels than industrial technologies, but lacks a performing catalytic process to reach commercialization. Here, we show that moderate CO2 amounts (R=CO2/(CO+CO2)=0.12) in the feed raise the HA productivity over copper‐iron catalysts carried on carbon nanofibers and promoted by potassium to a 3‐fold higher level than the state of the art. CO2 promotes copper dispersion and thus the formation of activated CO species, as in traditional methanol synthesis. Still, since its vicinity to iron is boosted, CO insertion into growing hydrocarbon chains prevails on hydrogenation, translating positive effects to HA production. Cascade zeolite‐catalyzed upgrading of methanol and olefins byproducts generates a breakthrough process forming 2.42 gHA h−1 gcat−1, which is 4‐times superior to the best systems, and tuning the HA nature based on the aluminosilicate topology. [ABSTRACT FROM AUTHOR]

The applicability of advanced composite materials with hierarchical structure that conjugate metal–organic frameworks (MOFs) with macroporous materials is commonly limited by their inferior mechanical properties. Here, a universal green synthesis method for the in situ growth of MOF nanocrystals within wood substrates is introduced. Nucleation sites for different types of MOFs are readily created by a sodium hydroxide treatment, which is demonstrated to be broadly applicable to different wood species. The resulting MOF/wood composite exhibits hierarchical porosity with 130 times larger specific surface area compared to native wood. Assessment of the CO2 adsorption capacity demonstrates the efficient utilization of the MOF loading along with similar adsorption ability to that of pure MOF. Compression and tensile tests reveal superior mechanical properties, which surpass those obtained for polymer substrates. The functionalization strategy offers a stable, sustainable, and scalable platform for the fabrication of multifunctional MOF/wood‐derived composites with potential applications in environmental‐ and energy‐related fields. [ABSTRACT FROM AUTHOR]

Porous nitrogen‐doped carbons (NCs) are sustainable alternatives to the toxic mercury‐based acetylene hydrochlorination catalysts applied in the manufacture of polyvinyl chloride. However, the application of NCs as metal‐free catalysts is hampered by their insufficient durability under industrially relevant process conditions. In particular, pore blockage leads to accelerated deactivation of NCs compared to the state‐of‐the‐art precious metal‐based systems. Herein, we develop a salt template‐assisted synthesis strategy coupled with chemical blowing to tune the textural properties of NCs, while preserving the N‐content and speciation. The addition of metal salts (i. e. Mg(OAc)2 or CaCO3) enhances gas evolution, leading to an increased formation of micro‐ and mesopores, while the in‐situ generated CaO/CaCl2 and MgO/MgCl2 develop auxiliary pore networks. Micropores are easily blocked during acetylene hydrochlorination, but meso‐ and macropores are structurally stable, enhancing the lifetime of hierarchical NCs by ca. 50 times compared to their non‐templated analogues, rivaling the stability of benchmark metal‐based catalysts. [ABSTRACT FROM AUTHOR]

Developing scalable systems and understanding dynamic behaviors are crucial for advancing the technological potential of multicomponent catalysts for CO2‐based methanol synthesis. In their Research Article (e202306563), Javier Pérez‐Ramírez and co‐workers show that the reaction‐induced restructuring of Pd‐In2O3/ZrO2 systems, prepared via impregnation, leads to a unique architecture that integrates the necessary acid‐base functionality of In2O3 with the H2 splitting ability of an InPd2 alloy, while also ensuring high stability. [ABSTRACT FROM AUTHOR]

Keywords: CO2-Hydrierung; Metall-Metalloxid-Wechselwirkungen; Methanolsynthese; Operando Analyse; Pd-In2O3/ZrO2 Katalysator DE CO2-Hydrierung Metall-Metalloxid-Wechselwirkungen Methanolsynthese Operando Analyse Pd-In2O3/ZrO2 Katalysator 1 1 1 10/12/23 20231016 NES 231016 B Developing scalable systems b and understanding dynamic behaviors are crucial for advancing the technological potential of multicomponent catalysts for CO SB 2 sb -based methanol synthesis. In their Research Article (e202306563), Javier Pérez-Ramírez and co-workers show that the reaction-induced restructuring of Pd-In SB 2 sb O SB 3 sb /ZrO SB 2 sb systems, prepared via impregnation, leads to a unique architecture that integrates the necessary acid-base functionality of In SB 2 sb O SB 3 sb with the H SB 2 sb splitting ability of an InPd SB 2 sb alloy, while also ensuring high stability. [Extracted from the article]

The potential implementation of ruthenium‐based catalysts in polyvinyl chloride production via acetylene hydrochlorination is hindered by their inferior activity and stability compared to gold‐based systems, despite their 4‐fold lower price. Combining in‐depth characterization and kinetic analysis we reveal the superior activity of ruthenium nanoparticles with an optimal size of 1.5 nm hosted on nitrogen‐doped carbon (NC) and identify their deactivation modes: 1) nanoparticle redispersion into inactive single atoms and 2) coke formation at the metal sites. Tuning the density of the NC carrier enables a catalytic encapsulation of the ruthenium nanoparticles into single layer graphene shells at 1073 K that prevent the undesired metal redispersion. Finally, we show that feeding O2 during acetylene hydrochlorination limits coke formation over the nanodesigned ruthenium catalyst, while the graphene layer is preserved, resulting in a stability increase of 20 times, thus rivalling the performance of gold‐based systems. [ABSTRACT FROM AUTHOR]

The lack of efficient catalysts prevents the electrocatalytic reduction of carbon dioxide from contributing to the pressing target of a carbon‐neutral economy. Indium‐modified copper nitride was identified as a stable electrocatalyst selective toward CO. In2O3/Cu3N showed a Faradaic efficiency of 80 % at 0.5 V overpotential for at least 50 h, in stark contrast to the very limited stability of the benchmark In2O3/Cu2O. Microfabricated systems allowed to correlate activity with highly stable interfaces in indium‐modified copper nitride. In contrast, fast diffusion of indium resulted in rapidly evolving interfaces in the case of the system based on oxide‐derived Cu. A metastable nitrogen species observed by spectroscopic means was proposed as the underlying cause leading to the unchanging interfaces. This work reveals the stabilizing properties of nitride‐derived copper toward high‐performance multicomponent catalysts. [ABSTRACT FROM AUTHOR]