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The synthesis of tertiary amines from alcohols (i.e. heptanol, dodecanol, cyclohexanol, benzylalcohol) and secondary amines (Me2NH (DMA), nPr2NH, nBu2NH) has been achieved in one step using trimetallic nanoparticles (NPs) displaying a magnetic core (Co4Ni6 and Fe3Ni7) and a Cu shell as both catalysts and heating agent in the presence of an alternating magnetic field. This methodology limits the redistribution reactions occurring on amines at high temperature leading to both much higher conversion and selectivity in the absence of solvent than usually observed using conventional heating. Moreover, Co4Ni6@Cu NPs were found moisture resistant, thereby allowing for performing the reaction with commercial DMA in water (40 % wt) with again high conversion and selectivity. [ABSTRACT FROM AUTHOR]

The synthesis of tertiary amines from alcohols (i.e. heptanol, dodecanol, cyclohexanol, benzylalcohol) and secondary amines (Me2NH (DMA), nPr2NH, nBu2NH) has been achieved in one step using trimetallic nanoparticles (NPs) displaying a magnetic core (Co4Ni6 and Fe3Ni7) and a Cu shell as both catalysts and heating agent in the presence of an alternating magnetic field. This methodology limits the redistribution reactions occurring on amines at high temperature leading to both much higher conversion and selectivity in the absence of solvent than usually observed using conventional heating. Moreover, Co4Ni6@Cu NPs were found moisture resistant, thereby allowing for performing the reaction with commercial DMA in water (40 % wt) with again high conversion and selectivity. [ABSTRACT FROM AUTHOR]

Dehydrochlorination (DHC) is of importance for modulating the physical properties of halogenated polymers. In this work, the DHC of commercial VDF‐CTFE (vinylidene fluoride‐co‐chlorotrifluoroethylene) (10 mol % CTFE) copolymer to VDF‐DB (vinylidene fluoride with unsaturated moieties‐Double Bond) was achieved in mild reaction conditions (150 °C and 3 bar hydrogen) using different supported nickel catalysts. A complete DHC was observed within four hours of the reaction. Additionally, a certain extent (8–35 %) of hydrodefluorination (HDF) of the polymer, a challenging transformation, can also be achieved after 72 hours. A plausible mechanism based on the nuclear magnetic resonance (NMR) spectroscopy study of DHC and HDF of VDF‐CTFE was proposed. The catalyst was recyclable and stable against leaching after at least three cycles. [ABSTRACT FROM AUTHOR]

A series of bimetallic Ni10–xCox (x: 2, 3, 4, 5) nanoparticles have been prepared using the organometallic approach from Ni-[iPrNC-(CH3)-NiPr]2 and Co-[N-(SiMe3)2]2(thf) precursors. Structural characterization by high-resolution transmission electron microscopy (HR-TEM), X-ray absorption spectroscopy (XAS), and X-ray diffraction (XRD) revealed a bimetallic structure with a face-centered cubic (fcc) Ni-rich core and ultrasmall (≤2 nm) hcp Co nanoparticles decorating it. Magnetic and magnetic hyperthermia properties were measured by vibrating sample magnetometry (VSM) and calorimetry, respectively. Moreover, the Ni7Co3 composition was shown to be a stable heterogeneous catalyst for diphenyl ether (DPE) hydrogenation under magnetic induction. Remarkably, the Ni7Co3 system before and after its decoration with a small amount of Ru (1 wt %) was transposed to the low-pressure hydrogenation of lignin-linkage models and lignin-oil molecules. The results showed that the system had moderate activity in cleaving different ether C–O bonds and was effective in upgrading lignin oils through hydrodeoxygenation (HDO), with a significant preference to produce cyclohexanols. This study represents a significant step toward applications of magnetic-induced catalysis in the field of biomass valorization. [ABSTRACT FROM AUTHOR]

The Sabatier reaction activated by high-frequency magnetic fields is a promising approach for the power-to-gas process because of expected high energy efficiencies and fast switch-on times. Recent progresses have been achieved by combining nanoparticles displaying both a high heating power and a good catalytic activity. Here, we alternatively use iron microparticles associated with our own-designed Ni/CeO2 catalyst. The heating agent is cheap and abundant, and we demonstrate that the presence of eddy currents in the system improves its heating performance. The contribution of eddy currents to global heating is successfully determined by an original protocol consisting in comparing a calorimetric and a high-frequency hysteresis loop-based method to measure heating power. In addition, the optimization of the catalyst bed using SiC-spacers limits sintering and thus improves the durability of the catalyst. The energy efficiency of the catalysis process, calculated as a function of coil consumption and gas flow, is clearly improved by the use of an air-cooled Litz wire coil. These improvements are a step forward toward the development of a cheap and efficient process for chemical energy storage. [ABSTRACT FROM AUTHOR]

We have studied the photoredox‐catalyzed hydrogen isotope exchange (HIE) reaction with deuterium or tritium gas as isotope sources and in situ formed transition metal nanoparticles as hydrogen atom transfer pre‐catalysts. By this means we have found synergistic reactivities applying two different HIE mechanisms, namely photoredox‐catalyzed and CH‐functionalization HIE leading to the synthesis of highly deuterated complex molecules. Finally, we adopted these findings successfully to tritium chemistry. [ABSTRACT FROM AUTHOR]

We have studied the photoredox‐catalyzed hydrogen isotope exchange (HIE) reaction with deuterium or tritium gas as isotope sources and in situ formed transition metal nanoparticles as hydrogen atom transfer pre‐catalysts. By this means we have found synergistic reactivities applying two different HIE mechanisms, namely photoredox‐catalyzed and CH‐functionalization HIE leading to the synthesis of highly deuterated complex molecules. Finally, we adopted these findings successfully to tritium chemistry. [ABSTRACT FROM AUTHOR]

The reduction of biomass‐derived compounds gives access to valuable chemicals from renewable sources, circumventing the use of fossil feedstocks. Herein, we describe the use of iron‐nickel magnetic nanoparticles for the reduction of biomass model compounds in aqueous media under magnetic induction. Nanoparticles with a hydrophobic ligand (FeNi3‐PA, PA=palmitic acid) have been employed successfully, and their catalytic performance is intended to improve by ligand exchange with lysine (FeNi3‐Lys and FeNi3@Ni‐Lys NPs) to enhance water dispersibility. All three catalysts have been used to hydrogenate 5‐hydroxymethylfurfural into 2,5‐bis(hydroxymethyl)furan with complete selectivity and almost quantitative yields, using 3 bar of H2 and a magnetic field of 65 mT in water. These catalysts have been recycled up to 10 times maintaining high conversions. Under the same conditions, levulinic acid has been hydrogenated to γ‐valerolactone, and 4'‐hydroxyacetophenone hydrodeoxygenated to 4‐ethylphenol, with conversions up to 70 % using FeNi3‐Lys, and selectivities above 85 % in both cases. This promising catalytic system improves biomass reduction sustainability by avoiding noble metals and expensive ligands, increasing energy efficiency via magnetic induction heating, using low H2 pressure, and proving good reusability while working in an aqueous medium. [ABSTRACT FROM AUTHOR]

In the present paper, we compare the activity, selectivity, and stability of a supported nickel catalyst in classical heating conditions and in magnetically activated catalysis by using iron wool as a heating agent. The catalyst, 5 wt% Ni supported on titania (Degussa P25), was prepared via an organometallic decomposition method and was thoroughly characterized by using elemental, microscopic, and diffraction techniques. In the event of magnetic induction heating, the % CO2 conversion reached a maximum of ~85% compared to ~78% for thermal conditions at a slightly lower temperature (~335 °C) than the thermal heating (380 °C). More importantly, both processes were found to be stable for 45 h on stream. Moreover, the effects of magnetic induction and classical heating over the catalyst evolution were discussed. This study demonstrated the potential of magnetic heating-mediated methanation, which is currently under investigation for the development of pilot-scale reactors. [ABSTRACT FROM AUTHOR]

Labelling of amino-acids is important for the production of deuterated proteins. However, aromatic amino-acid reduction is a common undesired process with noble-metal nanocatalysts. In this work, we describe a new NHC-stabilized water-soluble Pd/Ni system able to perform H/D exchange reactions in an enantiospecific fashion without reducing the aromatic ring of phenylalanine and tyrosine thanks to a synergetic Pd–Ni effect. [ABSTRACT FROM AUTHOR]

A new selective and efficient catalytic system for magnetically induced catalytic CO2 methanation was developed, composed of an abundant iron‐based heating agent, namely a commercial iron wool, combined with supported Nickel nanoparticles (Ni NPs) as catalysts. The effect of metal oxide support was evaluated by preparing different 10 wt % Ni catalyst (TiO2, ZrO2, CeO2, and CeZrO2) via organometallic decomposition route. As‐prepared catalysts were thoroughly characterized using powder X‐ray diffraction, electron microscopy, elemental analysis, vibrating sample magnetometer, and X‐ray photoelectron spectroscopy techniques. High conversion and selectivity toward methane were observed at mid‐temperature range, hence improving energy efficiency of the process with respect to the previous results under magnetic heating conditions. To gain further insight into the catalytic system, the effects of the synthesis method and of 0.5 wt % Ru doping were evaluated. Finally, the dynamic nature of magnetically induced heating was demonstrated through fast stop‐and‐go experiments, proving the suitability of this technology for the storage of intermittent renewable energy through P2G process. [ABSTRACT FROM AUTHOR]

Copper‐decorated iron carbide nanoparticles (Cu@ICNPs) are prepared following an organometallic approach, producing a multifunctional catalytic system that can be heated magnetically. ICNPs act as heating agents, generating thermal energy from the alternating current magnetic field in an extremely localized, rapid, and efficient manner, thereby heating and activating the catalytically active Cu‐containing NPs present at their surface. Upon exposure to magnetic induction, the Cu@ICNPs catalyst is capable of selectively hydrodeoxygenating aromatic aldehydes under mild observable conditions (≈100 °C, 3 bar H2), without hydrogenation of the aromatic ring. A large scope of benzylic and non‐benzylic aldehydes including key biomass‐derived platform chemicals could be effectively converted to valuable aromatic alkanes. In addition, the Cu@ICNPs catalytic system is found adaptive to intermittent electricity supply, which is of great interest when considering the use of alternative renewable energy sources. In contrast, Cu@ICNPs, ICNPs, or Cu NPs show low activity when heated conventionally, even up to 200 °C. This work demonstrates the possibility to use magnetic induction heating to perform challenging hydrodeoxygenation reactions at mild pressure and temperature with noble metal‐free catalysts, while being able to cope with fluctuating energy sources. [ABSTRACT FROM AUTHOR]

II–V semiconductor nanocrystals such as Cd3P2 and Zn3P2 have enormous potential as materials in next-generation optoelectronic devices requiring active optical properties across the visible and infrared range. To date, this potential has been unfulfilled due to their inherent instability with respect to air and moisture. Core-shell system Cd3P2/Zn3P2 is synthesized and studied from structural (morphology, crystallinity, shell diameter), chemical (composition of core, shell, and ligand sphere), and optical perspectives (absorbance, emission-steady state and time resolved, quantum yield, and air stability). The improvements achieved by coating with Zn3P2 are likely due to its identical crystal structure to Cd3P2 (tetragonal), highlighting the key role crystallographic concerns play in creating cutting edge core-shell NCs. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (NPs) are attractive both for their fundamental properties and for their potential in a variety of applications ranging from nanomedicine and biology to micro/nanoelectronics and catalysis. While these fields are dominated by the use of iron oxides, reduced metal NPs are of interest since they display high magnetization and adjustable anisotropy according to their size, shape and composition. The use of organometallic precursors makes it possible to adjust the size, shape (sphere, cube, rod, wire, urchin, ...) and composition (alloys, core–shell, composition gradient, dumbbell, ...) of the resulting NPs and hence their magnetic properties. We discuss here the synthesis of magnetic metal NPs from organometallic precursors carried out in Toulouse, as well as their associated properties and their potential in applications. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (NPs) are attractive both for their fundamental properties and for their potential in a variety of applications ranging from nanomedicine and biology to micro/nanoelectronics and catalysis. While these fields are dominated by the use of iron oxides, reduced metal NPs are of interest since they display high magnetization and adjustable anisotropy according to their size, shape and composition. The use of organometallic precursors makes it possible to adjust the size, shape (sphere, cube, rod, wire, urchin, ...) and composition (alloys, core–shell, composition gradient, dumbbell, ...) of the resulting NPs and hence their magnetic properties. We discuss here the synthesis of magnetic metal NPs from organometallic precursors carried out in Toulouse, as well as their associated properties and their potential in applications. [ABSTRACT FROM AUTHOR]

Copper chromite is decorated with iron carbide nanoparticles, producing a magnetically activatable multifunctional catalytic system. This system (ICNPs@Cu2Cr2O5) can reduce aromatic ketones to aromatic alcohols when exposed to magnetic induction. Under magnetic excitation, the ICNPs generate locally confined hot spots, selectively activating the Cu2Cr2O5 surface while the global temperature remains low (≈80 °C). The catalyst selectively hydrogenates a scope of benzylic and non‐benzylic ketones under mild conditions (3 bar H2, heptane), while ICNPs@Cu2Cr2O5 or Cu2Cr2O5 are inactive when the same global temperature is adjusted by conventional heating. A flow reactor is presented that allows the use of magnetic induction for continuous‐flow hydrogenation at elevated pressure. The excellent catalytic properties of ICNPs@Cu2Cr2O5 for the hydrogenation of biomass‐derived furfuralacetone are conserved for at least 17 h on stream, demonstrating for the first time the application of a magnetically heated catalyst to a continuously operated hydrogenation reaction in the liquid phase. [ABSTRACT FROM AUTHOR]

Copper chromite is decorated with iron carbide nanoparticles, producing a magnetically activatable multifunctional catalytic system. This system (ICNPs@Cu2Cr2O5) can reduce aromatic ketones to aromatic alcohols when exposed to magnetic induction. Under magnetic excitation, the ICNPs generate locally confined hot spots, selectively activating the Cu2Cr2O5 surface while the global temperature remains low (≈80 °C). The catalyst selectively hydrogenates a scope of benzylic and non‐benzylic ketones under mild conditions (3 bar H2, heptane), while ICNPs@Cu2Cr2O5 or Cu2Cr2O5 are inactive when the same global temperature is adjusted by conventional heating. A flow reactor is presented that allows the use of magnetic induction for continuous‐flow hydrogenation at elevated pressure. The excellent catalytic properties of ICNPs@Cu2Cr2O5 for the hydrogenation of biomass‐derived furfuralacetone are conserved for at least 17 h on stream, demonstrating for the first time the application of a magnetically heated catalyst to a continuously operated hydrogenation reaction in the liquid phase. [ABSTRACT FROM AUTHOR]

Today, hydrogen mainly originates from fossil sources (gas, oil, and coal). Room temperature water electrolysis is an interesting alternative for renewable electricity storage, even if it is well-known that high-temperature systems are more efficient. To address this issue, we studied different non-platinum group metal (non-PGM) catalysts for alkaline oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) by recording cyclic voltamperograms with a rotating disk electrode set up. Physicochemical characterizations of Ni-based and FeNi3-based catalysts were performed using transmission electron microscopy, X-ray diffraction (XRD), and inductively coupled plasma mass spectroscopy (ICP-MS). Ni synthesized by the hot injection method is a good catalyst for HER, yet still less active than Pt/C. FeNi3 with and without a Ni surface doping is very good OER catalysts, slightly better than commercial unsupported IrO2. Electrochemical tests under alternating magnetic field (AMF) using these nanoparticles are ongoing, as these materials are compatible with AMF activation. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of the new compounds K(P3C2R2) [R=Ad (2), sBu (3)] and In(P3C2R2) [R=Ad (4), Mes (5)] are described. Further, the synthesis of indium nanoparticles via a single‐source precursor approach using In(1,2,4‐P3C2tBu2) (1) as precursor is reported. These nanoparticles were characterized by TEM, HRTEM, EDX, XRD, NMR, and optical spectroscopy. [ABSTRACT FROM AUTHOR]

Bimetallic FeNi3 nanoparticles (NPs) enriched with Ni (FeNi3@Ni) have been used to perform the hydrodeoxygenation reaction (HDO) and cleavage of lignocellulose-derived products in solution using magnetic induction. The application of a high frequency magnetic field induces high temperatures at the surface of the NPs that drive the catalytic reaction. The activation of the C–O bond of several functional groups was studied. FeNi3@Ni NPs, which act both as catalysts and magnetic heating agents, catalyzed the total conversion of furfural and 5-hydroxymethyl furfural into respectively 2-methylfuran and 2,5-dimethylfuran under mild conditions (12 mol% catalyst, 3 bar H2, 49 mT). The oligomerization of cyclopentanone, derived from furfural, was also achieved to yield C10 and C15 oligocyclopentyl products. Under the same conditions, diphenyl and benzyl phenyl ether, used as model molecules of polymeric lignin, were cleaved at 86% and 100% conversion respectively, to yield a mixture of hydrogenolysis and hydrogenated products. This is explained by the presence of Ni at the surface of the NP that favors the hydrogenation of the aromatic rings. The short reaction times and simplicity of the experimental set-up highlight the advantages of the application of magnetic heating for difficult transformations in solution, here the catalytic treatment of biomass-derived molecules. [ABSTRACT FROM AUTHOR]

We report the dramatic impact of the addition of N‐heterocyclic carbenes (NHCs) on the reactivity and selectivity of heterogeneous Ru catalysts in the context of C−H activation reactions. Using a simple and robust method, we prepared a series of new air‐stable catalysts starting from commercially available Ru on carbon (Ru/C) and differently substituted NHCs. Associated with C−H deuteration processes, depending on Ru/C‐NHC ratios, the chemical outcome can be controlled to a large extent. Indeed, tuning the reactivity of the Ru catalyst with NHC enabled: 1) increased chemoselectivity and the regioselectivity for the deuteration of alcohols in organic media; 2) the synthesis of fragile pharmaceutically relevant deuterated heterocycles (azine, purine) that are otherwise completely reduced using unmodified commercial catalysts; 3) the discovery of a novel reactivity for such heterogeneous Ru catalysts, namely the selective C‐1 deuteration of aldehydes. [ABSTRACT FROM AUTHOR]

Radiolabelling is fundamental in drug discovery and development as it is mandatory for preclinical ADME studies and late‐stage human clinical trials. Herein, a general, effective, and easy to implement method for the multiple site incorporation of deuterium and tritium atoms using the commercially available and air‐stable iridium precatalyst [Ir(COD)(OMe)]2 is described. A large scope of pharmaceutically relevant substructures can be labelled using this method including pyridine, pyrazine, indole, carbazole, aniline, oxa‐/thia‐zoles, thiophene, but also electron‐rich phenyl groups. The high functional group tolerance of the reaction is highlighted by the labelling of a wide range of complex pharmaceuticals, containing notably halogen or sulfur atoms and nitrile groups. The multiple site hydrogen isotope incorporation has been explained by the in situ formation of complementary catalytically active species: monometallic iridium complexes and iridium nanoparticles. [ABSTRACT FROM AUTHOR]

We report the dramatic impact of the addition of N‐heterocyclic carbenes (NHCs) on the reactivity and selectivity of heterogeneous Ru catalysts in the context of C−H activation reactions. Using a simple and robust method, we prepared a series of new air‐stable catalysts starting from commercially available Ru on carbon (Ru/C) and differently substituted NHCs. Associated with C−H deuteration processes, depending on Ru/C‐NHC ratios, the chemical outcome can be controlled to a large extent. Indeed, tuning the reactivity of the Ru catalyst with NHC enabled: 1) increased chemoselectivity and the regioselectivity for the deuteration of alcohols in organic media; 2) the synthesis of fragile pharmaceutically relevant deuterated heterocycles (azine, purine) that are otherwise completely reduced using unmodified commercial catalysts; 3) the discovery of a novel reactivity for such heterogeneous Ru catalysts, namely the selective C‐1 deuteration of aldehydes. [ABSTRACT FROM AUTHOR]

Radiolabelling is fundamental in drug discovery and development as it is mandatory for preclinical ADME studies and late‐stage human clinical trials. Herein, a general, effective, and easy to implement method for the multiple site incorporation of deuterium and tritium atoms using the commercially available and air‐stable iridium precatalyst [Ir(COD)(OMe)]2 is described. A large scope of pharmaceutically relevant substructures can be labelled using this method including pyridine, pyrazine, indole, carbazole, aniline, oxa‐/thia‐zoles, thiophene, but also electron‐rich phenyl groups. The high functional group tolerance of the reaction is highlighted by the labelling of a wide range of complex pharmaceuticals, containing notably halogen or sulfur atoms and nitrile groups. The multiple site hydrogen isotope incorporation has been explained by the in situ formation of complementary catalytically active species: monometallic iridium complexes and iridium nanoparticles. [ABSTRACT FROM AUTHOR]

Magnetically induced catalysis can be promoted taking advantage of optimal heating properties from the magnetic nanoparticles to be employed. However, when unprotected, these heating agents that are usually air‐sensitive, get sintered under the harsh catalytic conditions. In this context, we present, to the best of our knowledge, the first example of air‐stable magnetic nanoparticles that: 1) show excellent performance as heating agents in the CO2 methanation catalyzed by Ni/SiRAlOx, with CH4 yields above 95 %, and 2) do not sinter under reaction conditions. To attain both characteristics we demonstrate, first the exchange‐coupled magnetic approach as an alternative and effective way to tune the magnetic response and heating efficiency, and second, the chemical stability of cuboctahedron‐shaped core–shell hard CoFe2O4–soft Fe3O4 nanoparticles. [ABSTRACT FROM AUTHOR]

Magnetically induced catalysis can be promoted taking advantage of optimal heating properties from the magnetic nanoparticles to be employed. However, when unprotected, these heating agents that are usually air‐sensitive, get sintered under the harsh catalytic conditions. In this context, we present, to the best of our knowledge, the first example of air‐stable magnetic nanoparticles that: 1) show excellent performance as heating agents in the CO2 methanation catalyzed by Ni/SiRAlOx, with CH4 yields above 95 %, and 2) do not sinter under reaction conditions. To attain both characteristics we demonstrate, first the exchange‐coupled magnetic approach as an alternative and effective way to tune the magnetic response and heating efficiency, and second, the chemical stability of cuboctahedron‐shaped core–shell hard CoFe2O4–soft Fe3O4 nanoparticles. [ABSTRACT FROM AUTHOR]

A key challenge for designing hybrid materials is the development of chemical tools to control the organization of inorganic nanoobjects at low scales, from mesoscopic (~µm) to nanometric (~nm). So far, the most efficient strategy to align assemblies of nanoparticles consists in a bottom-up approach by decorating block copolymer lamellae with nanoobjects. This well accomplished procedure is nonetheless limited by the thermodynamic constraints that govern copolymer assembly, the entropy of mixing as described by the Flory–Huggins solution theory supplemented by the critical influence of the volume fraction of the block components. Here we show that a completely different approach can lead to tunable 2D lamellar organization of nanoparticles with homopolymers only, on condition that few elementary rules are respected: 1) the polymer spontaneously allows a structural preorganization, 2) the polymer owns functional groups that interact with the nanoparticle surface, 3) the nanoparticles show a surface accessible for coordination. Precise organization of nanoparticles and polymers for the design of hybrid materials remains a challenging task. Here, the authors show a convenient way to organize nanoobjects by preorganization of inorganic particles in presence of a functional peptidic homopolymer. [ABSTRACT FROM AUTHOR]

Magnetic heating by nanoparticles has recently been successfully employed in heterogeneous catalysis. In such processes, the maximum temperature that can be reached depends on the Curie temperature (Tc) of the heating material. Here, in order to extend the range of accessible temperatures and consequently the range of possible reactions, to those requiring high temperatures, we developed and fully characterized a series of FeCo nanoparticles containing different concentrations of cobalt, in order to tune their magnetic properties and Tc. Their efficiency is compared to that of iron carbide nanoparticles, which display a lower Tc. Specific absorption rate (SAR) measurements as a function of temperature, performed using a homemade pyrometer-based setup, clearly show that although the heating power of iron carbide nanoparticles is higher at room temperature it decreases more rapidly with temperature than that of iron cobalt nanoparticles, in agreement with their lower Tc. In a showcase, Fe0.5Co0.5 nanoparticles allow, in addition to CO2 hydrogenation, dry reforming of propane and methane, and dehydrogenation of propane, these reactions requiring temperatures of 350 °C, 600 °C, and 700 °C, respectively. Furthermore, the use of Fe0.5Co0.5 nanoparticles is less energy demanding, as it allows carrying out CO2 hydrogenation at lower magnetic fields and at frequencies as low as 100 kHz. Dry reforming of methane and propane were carried out in the presence of a Ni nanoparticle-based catalyst, whereas dehydrogenation of propane required as a catalyst PtSn nanoparticles synthesized through an organometallic route. Fe0.5Co0.5 nanoparticles can therefore be used as universal heating agents allowing reactions to be performed up to ca. 700 °C upon association with the appropriate catalyst. [ABSTRACT FROM AUTHOR]

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

Induction heating of magnetic nanoparticles (NPs) is a method to activate heterogeneous catalytic reactions. It requires nano‐objects displaying high heating power and excellent catalytic activity. Here, using a surface engineering approach, bimetallic NPs are used for magnetically induced CO2 methanation, acting both as heating agent and catalyst. The organometallic synthesis of Fe30Ni70 NPs displaying high heating powers at low magnetic field amplitudes is described. The NPs are active but only slightly selective for CH4 after deposition on SiRAlOx owing to an iron‐rich shell (25 mL min−1, 25 mT, 300 kHz, conversion 71 %, methane selectivity 65 %). Proper surface engineering consisting of depositing a thin Ni layer leads to Fe30Ni70@Ni NPs displaying a very high activity for CO2 hydrogenation and a full selectivity. A quantitative yield in methane is obtained at low magnetic field and mild conditions (25 mL min−1, 19 mT, 300 kHz, conversion 100 %, methane selectivity 100 %). [ABSTRACT FROM AUTHOR]

Induction heating of magnetic nanoparticles (NPs) is a method to activate heterogeneous catalytic reactions. It requires nano‐objects displaying high heating power and excellent catalytic activity. Here, using a surface engineering approach, bimetallic NPs are used for magnetically induced CO2 methanation, acting both as heating agent and catalyst. The organometallic synthesis of Fe30Ni70 NPs displaying high heating powers at low magnetic field amplitudes is described. The NPs are active but only slightly selective for CH4 after deposition on SiRAlOx owing to an iron‐rich shell (25 mL min−1, 25 mT, 300 kHz, conversion 71 %, methane selectivity 65 %). Proper surface engineering consisting of depositing a thin Ni layer leads to Fe30Ni70@Ni NPs displaying a very high activity for CO2 hydrogenation and a full selectivity. A quantitative yield in methane is obtained at low magnetic field and mild conditions (25 mL min−1, 19 mT, 300 kHz, conversion 100 %, methane selectivity 100 %). [ABSTRACT FROM AUTHOR]

Purpose: Technologies with low environmental impacts and promoting renewable energy sources are required to meet the energetic demand while facing the increase of gas emissions associated to the greenhouse effect and the depletion of fossil fuels. CO2 methanation activated by magnetic heating has recently been reported as a highly efficient and innovative power-to-gas technology in a perspective of successful renewable energy storage and carbon dioxide valorisation. In this work, the life cycle assessment (LCA) of this process is performed, in order to highlight the environmental potential of the technology, and its competitivity with in respect to conventional heating technologies. Methods: The IMPACT 2002+ was used for this LCA. The process studied integrates methanation, water electrolysis and CO2 capture and separation. This "cradle-to-gate" LCA study does not consider the use of methane, which is the reaction product. The functional unit used is the energy content of the produced CH4. The LCA was carried out using the energy mix data for the years 2020 and 2050 as given by the French Agency for Environment and Energy management (ADEME). Consumption data were either collected from literature or obtained from the LPCNO measurements as discussed by Marbaix (2019). The environmental impact of the CO2 methanation activated by magnetic heating was compared with the environmental impact of a power-to-gas plant using conventional heating (Helmeth) and considering the environmental impact of the natural gas extraction. Results: It is shown that the total flow rate of reactants, the source of CO2 and the energy mix play a major role on the environmental impact of sustainable CH4 production, whereas the lifetime of the considered catalyst has no significant influence. As a result of the possible improvements on the above-mentioned parameters, the whole process is expected to reduce by 75% in its environmental impact toward 2050. This illustrates the high environmental potential of the methanation activated by magnetic heating when coupled with industrial exhausts and renewable electricity production. Conclusions: The technology is expected to be environmentally competitive compared with existing similar processes using external heating sources with the additional interest of being extremely dynamic in response, in line with the intermittency of renewable energy production. [ABSTRACT FROM AUTHOR]

The quest of exploring alternative materials for the replacement of toxic cadmium- and lead-based quantum dots (QDs) is necessary for envisaging a sustainable future but remains highly challenging. Tackling this issue, we present the synthesis of Zn3P2 nanocrystals (NCs) of unprecedented quality. New, reactive zinc precursors yield highly crystalline, colloidally stable particles, exhibiting oxide-free surfaces, size tunability and outstanding optical properties relative to previous reports of zinc phosphide QDs. [ABSTRACT FROM AUTHOR]

The preparation of N‐heterocyclic carbene‐stabilized iridium nanoparticles and their application in hydrogen isotope exchange reactions is reported. These air‐stable and easy‐to‐handle iridium nanoparticles showed a unique catalytic activity, allowing selective and efficient hydrogen isotope incorporation on anilines using D2 or T2 as isotopic source. The usefulness of this transformation has been demonstrated by the deuterium and tritium labeling of diverse complex pharmaceuticals. [ABSTRACT FROM AUTHOR]

The preparation of N‐heterocyclic carbene‐stabilized iridium nanoparticles and their application in hydrogen isotope exchange reactions is reported. These air‐stable and easy‐to‐handle iridium nanoparticles showed a unique catalytic activity, allowing selective and efficient hydrogen isotope incorporation on anilines using D2 or T2 as isotopic source. The usefulness of this transformation has been demonstrated by the deuterium and tritium labeling of diverse complex pharmaceuticals. [ABSTRACT FROM AUTHOR]