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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]

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]

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]

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 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]

Magnetic heating has recently been demonstrated as an efficient way to perform catalytic reactions after deposition of the heating agent and the catalyst on a support. Here we show that in solution, and under mild conditions of mean temperature and pressure, it is possible to use magnetic heating to carry out transformations that are otherwise performed heterogeneously at high pressure and/or high temperature. As a proof of concept, we chose the hydrodeoxygenation of acetophenone derivatives and of biomass‐derived molecules, namely furfural and hydroxymethylfurfural. These reactions are difficult, require heterogeneous catalysts and high pressures, and, to the best of our knowledge, have no precedent in standard solution. Here, hydrodeoxygenations are fully selective under mild conditions (3 bar H2, moderate mean temperature of the solvent). The reason for this reactivity is the fast heating of the particles well above the boiling temperature of the solvent and the local creation of hot spots surrounded by a vapor layer, in which high temperature and pressure may be present. This technology may be practicable for many organic transformations. [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]

The article focuses on bridging the gap between homogeneous and heterogeneous catalysis. The application of concepts of homogeneous catalysis to heterogeneous catalysis and vice versa constitutes an area of current interest. Nuclear Magnetic Resonance technique has been used to derive at the mentioned results. It has concluded that exploring both the liquid and solid-state activity of a catalyst may help to bridge the gap between the homogeneous and heterogeneous catalysis and to provide additional information about the reaction mechanisms.