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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]

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 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]

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]

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]

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]

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]

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]

The use of magnetic nanoparticles to convert electromagnetic energy into heat is known to be a key strategy for numerous biomedical applications but is also an approach of growing interest in the field of catalysis. The heating efficiency of magnetic nanoparticles is limited by the poor magnetic properties of most of them. Here we show that the new generation of iron carbide nanoparticles of controlled size and with over 80 % crystalline Fe2.2C leads to exceptional heating properties, which are much better than the heating properties of currently available nanoparticles. Associated to catalytic metals (Ni, Ru), iron carbide nanoparticles submitted to magnetic excitation very efficiently catalyze CO2 hydrogenation in a dedicated continuous-flow reactor. Hence, we demonstrate that the concept of magnetically induced heterogeneous catalysis can be successfully applied to methanation of CO2 and represents an approach of strategic interest in the context of intermittent energy storage and CO2 recovery. [ABSTRACT FROM AUTHOR]

This comprehensive review explores the potential of radio frequency (RF) induction heating in chemical reactions, explicitly focusing on magnetically induced catalysis using magnetic nanoparticles (NPs). We trace the recent historical progress of induction heating and highlight the advancements in liquid and gas‐phase reactions, particularly in its integration with heterogeneous catalysis. The review finds that induction heating profoundly impacts reaction kinetics, and selectivity, and can even reduce overpotentials in electrocatalytic processes. A final outlook unveils the challenges and opportunities associated with aspects such as fundamental research and reactor design, with a particular focus on expanding its use to higher pressures and necessary optimizations to improve energy efficiency. Moreover, it highlights the pressing need for standardized reporting in induction‐heated catalysis. The study underscores the significance of this brand‐new field in developing efficient and sustainable catalytic processes, which are essential for meeting the growing demand for clean energy and sustainable chemical production. [ABSTRACT FROM AUTHOR]

We report a tunable organometallic synthesis of monodisperse iron carbide and core/shell iron/iron carbide nanoparticles displaying a high magnetization and good air-stability. This process based on the decomposition of Fe(CO)5 on Fe(0) seeds allows the control of the amount of carbon diffused and therefore the tuning of nanoparticles magnetic anisotropy. This results in unprecedented hyperthermia properties at moderate magnetic fields, in the range of medical treatments. [ABSTRACT FROM AUTHOR]