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Methanesulfonic acid, an industrially useful chemical, is made directly from methane Methane, the major component in natural gas, is one of the most difficult molecules to activate in a controlled manner, because almost any initial oxidation product is easier to oxidize than methane itself and most of the product is carbon dioxide. Instead, methane is currently converted to syngas, a mixture of carbon monoxide and hydrogen, from which many useful products, such as methanol or Fischer-Tropsch hydrocarbons, can be synthesized in subsequent steps. However, syngas production is characterized by severe economies of scale. Economical plants must be very large, such as the so-called “MegaMethanol” plants or the Fischer-Tropsch Pearl complex in Qatar, where the total annual hydrocarbon production exceeds 10 million metric tons (MT). Thus, direct approaches for converting methane to valuable products that are also economical on a smaller scale are of extreme interest. Such processes could rescue so-called stranded natural gas that is produced in too small an amount and is too remote to transport economically. In the worst case, stranded natural gas extracted with other fossil fuels is burned (“flared”; see the photo). On page 1326 of this issue, Díaz-Urrutia and Ott ( 1 ) at the Grillo company report a direct process that converts methane directly to methanesulfonic acid, a chemical with many industrial uses.

In its nanoparticulate form, corundum (α-Al₂O₃) could lead to several applications. However, its production into nanoparticles (NPs) is greatly hampered by the high activation energy barrier for its formation from cubic close-packed oxides and the sporadic nature of its nucleation. We report a simple synthesis of nanometer-sized α-Al₂O₃ (particle diameter ~13 nm, surface areas ~140 m² g−1) by the mechanochemical dehydration of boehmite (γ-AlOOH) at room temperature. This transformation is accompanied by severe microstructural rearrangements and might involve the formation of rare mineral phases, diaspore and tohdite, as intermediates. Thermodynamic calculations indicate that this transformation is driven by the shift in stability from boehmite to α-Al₂O₃ caused by milling impacts on the surface energy. Structural water in boehmite plays a crucial role in generating and stabilizing α-Al₂O₃ NPs.

The synthesis of 2,5-dimethylfuran (DMF) from 5-hydroxymethylfurfural (HMF) is a highly attractive route to a renewable fuel. However, achieving high yields in this reaction is a substantial challenge. Here it is described how PtCo bimetallic nanoparticles with diameters of 3.6 ± 0.7 nm can solve this problem. Over PtCo catalysts the conversion of HMF was 100% within 10 min and the yield to DMF reached 98% after 2 h, which substantially exceeds the best results reported in the literature. Moreover, the synthetic method can be generalized to other bimetallic nanoparticles encapsulated in hollow carbon spheres. Although producing 2,5-dimethylfuran (DMF) from 5-hydroxymethylfurfural (HMF) is an attractive way to synthesize renewable fuels, achieving high yields for this reaction has proved difficult. PtCo bimetallic nanoparticle catalysts embedded in hollow carbon nanospheres now show improved catalytic performance for the hydrogenolysis of HMF to DMF (98% yield after 2 hours).

The reduction in noble metal content for efficient oxygen evolution catalysis is a crucial aspect towards the large scale commercialisation of polymer electrolyte membrane electrolyzers. Since catalytic stability and activity are inversely related, long service lifetime still demands large amounts of low-abundant and expensive iridium. In this manuscript we elaborate on the concept of maximizing the utilisation of iridium for the oxygen evolution reaction. By combining different tin oxide based support materials with liquid atomic layer deposition of iridium oxide, new possibilities are opened up to grow thin layers of iridium oxide with tuneable noble metal amounts. In-situ , time- and potential-resolved dissolution experiments reveal how the stability of the substrate and the catalyst layer thickness directly affect the activity and stability of deposited iridium oxide. Based on our results, we elaborate on strategies how to obtain stable and active catalysts with maximized iridium utilisation for the oxygen evolution reaction and demonstrate how the activity and durability can be tailored correspondingly. Our results highlight the potential of utilizing thin noble metal films with earth abundant support materials for future catalytic applications in the energy sector.

Carbon supported phosphoric acid (H 3 PO 4 /C) was found to be a more productive catalyst for the gas-phase synthesis of the diesel fuel additive/substitute oxymethylene ethers (OME) as compared to benchmark zeolite catalysts. In this contribution, the performance of catalysts H 3 PO 4 /C and related H 2 PO 4 − /C and HPO 4 2− /C materials in OME synthesis from methanol and formaldehyde is described. Graphic Abstract

▪ Abstract  In recent years substantial progress has been made in the control of the properties of porous materials on the nano-, meso-, and macroscale. The feature of solids can, in favorable cases, be tailored to such an extent that one is justified in using the term engineering of porous catalytic materials. This review highlights recent developments concerning (a) the control of the pore structure of zeolites, (b) the creation of single site type catalysts based on ordered mesoporous oxides, (c) the catalytic potential of porous coordination compounds, and (d) the advances with respect to direct production of desired shapes of porous catalytic materials.

The conversion of carbon-based solids, like non-recyclable plastics, biomass, and coal, into small molecules appears attractive from different points of view. However, the strong carbon–carbon bonds in these substances pose a severe obstacle, and thus—if such reactions are possible at all—high temperatures are required 1 – 5 . The Bergius process for coal conversion to hydrocarbons requires temperatures above 450 °C 6 , pyrolysis of different polymers to pyrolysis oil is also typically carried out at similar temperatures 7 , 8 . We have now discovered that efficient hydrogenation of different solid substrates with the carbon-based backbone to light hydrocarbons can be achieved at room temperature by ball milling. This mechanocatalytic method is surprisingly effective for a broad range of different carbon substrates, including even diamond. The reaction is found to proceed via a radical mechanism, as demonstrated by reactions in the presence of radical scavengers. This finding also adds to the currently limited knowledge in understanding mechanisms of reactions induced by ball milling. The results, guided by the insight into the mechanism, could induce more extended exploration to broaden the application scope and help to address the problem of plastic waste by a mechanocatalytic approach. Conventional methods to gasify or liquefy carbon-based polymers use high temperatures because of carbon–carbon bond stability. Here, the authors describe a mechanochemical ball milling method to break carbon–carbon bonds without heating.

The copper‐catalyzed electrochemical CO2 reduction reaction represents an elegant pathway to reduce CO2 emissions while producing a wide range of valuable hydrocarbons. The selectivity for these products depends strongly on the structure and morphology of the copper catalyst. However, continued deactivation during catalysis alters the obtained product spectrum. In this work, we report on the stabilizing effect of three different carbon supports with unique pore structures. The influence of pore structure on stability and selectivity was examined by high‐angle annular dark field scanning transmission electron microscopy and gas chromatography measurements in a micro‐flow cell. Supporting particles into confined space was found to increase the barrier for particle agglomeration during 20 h of chronopotentiometry measurements at 100 mA cm−2 resembling long‐term CO2 reduction conditions. We propose a catalyst design preventing coalescence and agglomeration in harsh electrochemical reaction conditions, exemplarily demonstrated for the electrocatalytic CO2 reduction. With this work, we provide important insights into the design of stable CO2 electrocatalysts that can potentially be applied to a wide range of applications. Role of support: Post‐catalytic evaluation of three different carbon‐supported Cu CO2 reduction catalysts revealed a location‐dependent stabilization of nanoparticles in the support, with pore confinement showing anti‐agglomeration capabilities. Measured faradaic efficiency put previously reported particle size‐selectivity relations into question and highlight the need for post‐catalytic evaluation to elucidate structure‐selectivity relations.

Carbon-protected magnetic nanoparticles exhibit long-term stability in acid or alkaline medium, good biocompatibility, and high saturation magnetization. As a result, they hold great promise for magnetic resonance imaging, photothermal therapy, etc. However, since pyrolysis, which is often required to convert the carbon precursors to carbon, typically leads to coalescence of the nanoparticles, the obtained carbon-protected magnetic nanoparticles are usually sintered as a non-dispersible aggregation. We have successfully synthesized discrete, dispersible, and uniform carbon-protected magnetic nanoparticles via a precise surface/interface nano-engineering approach. Remarkably, the nanoparticles possess excellent water-dispersibility, biocompatibility, a high T2 relaxivity coefficient （384 mM^-1·s^-1）, and a high photothermal heating effect. Furthermore, they can be used as multifunctional core components suited for future extended investigation in early diagnosis, detection and therapy, catalysis, separation, and magnetism.

THE recent synthesis of silica-based mesoporous materials 1,2 by the cooperative assembly of periodic inorganic and surfactant-based structures has attracted great interest because it extends the range of molecular-sieve materials into the very-large-pore regime. If the synthetic approach can be generalized to transition-metal oxide mesostructures, the resulting nanocomposite materials might find applications in electrochromic or solid-electrolyte devices 3,4 , as high-surface-area redox catalysts 5 and as substrates for biochemical separations. We have proposed recently 6 that the matching of charge density at the surfactant/inorganic interfaces governs the assembly process; such co-organization of organic and inorganic phases is thought to be a key aspect of biomineralization 7 . Here we report a generalized approach to the synthesis of periodic mesophases of metal oxides and cationic or anionic surfactants under a range of pH conditions. We suggest that the assembly process is controlled by electrostatic complementarity between the inorganic ions in solution, the charged surfactant head groups and—when these charges both have the same sign—inorganic counterions. We identify a number of different general strategies for obtaining a variety of ordered composite materials.