Copper‐Decorated Iron Carbide Nanoparticles Heated by Magnetic Induction as Adaptive Multifunctional Catalysts for the Selective Hydrodeoxygenation of Aldehydes

Abstract

an important transformation for the fine chemical and pharmaceutical industries, and is also considered an important enabler for chemical energy conversion and especially for the upgrading of biomass feedstock to value-added chemicals. [1] In particular, the selective hydrodeoxygenation of renewable platform chemicals such as furfural, hydroxymethylfurfural and vanillin has attracted tremendous attention in the past years. [2] This requires selectively hydrodeoxygenating aromatic aldehydes, while leaving the aromaticity of the ring untouched. To provide alternatives to stoichiometric methods that involve toxic reagents and hazardous wastes (Wolff-Kishner, [3] Clemmensen [4] ), recent efforts focused on the development of catalytic systems possessing such reactivity. While noble metal catalysts often suffer from low selectivity due to undesired aromatic hydrogenation, [5] promising results for the selective reduction of aromatic carbonyls have been obtained using bimetallic nanoparticles as well as 3d metal catalysts. [6] However, the development of catalytic systems fulfilling the requirements of high yields, selectivity, stability, productivity, safety, and environmental compatibility remains a challenge. [7] In addition, with the rise of alternative renewable energy sources, the permanent evolution of catalysts and catalytic processes is crucial to face the inevitable variations in electricity production. In particular, energy efficiency, benignity of reaction conditions, and adaptivity to intermittent energy supply are parameters of ever-increasing importance. [8] In this context, magnetic induction offers the possibility to heat directly magnetic nanoparticles (e.g., catalysts) in an extremely localized, rapid, and energy efficient manner, saving the need to heat the complete reactor environment (solvent, reactor parts, etc.). [8c,9] In turn, this may result in milder overall process temperatures and lower energy consumption. In addition, the rapid heating and cooling of nanoparticles activated by magnetic induction is of great interest to address the challenges associated to the use of fluctuating renewable energy. Magnetic induction is a mature technology that is used for decades also on industrial scale (e.g., metallurgy), and that can thus offer promising new perspectives for process intensification, in particular of small to medium-size processes requiring constant heating.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 H 2 ), without hydrogenatio...

Hydrogen Spillover-Driven Dynamic Evolution and Migration of Iron Oxide for Structure Regulation of Versatile Magnetic Nanocatalysts

“…Supported Pd nanomaterials have been shown as one of the most powerful catalysts for the selective hydrogenation reaction. , In addition, the use of magnetic induction heating of magnetic nanomaterials in catalytic reactions has recently emerged as a hot field. − This localized heating technology is significant in facilitating organic transformations under mild conditions. Hence, we investigated the Pd-loaded split core–shell catalyst (M2) for the selective hydrogenation of crotonaldehyde to butanal under the induction of an alternative magnetic field.…”

Adaptive Catalytic Systems for Chemical Energy Conversion

“…Such immediate response from the catalyst to the magnetic field is of great interest to tackle the industrial challenges associated with intermittent electricity supply. Subsequently, it was demonstrated that inversely catalytically active metal particles can be deposited also on ICNPs or other suitable magnetic NPs potentially allowing for even more direct heat dissipation (e.g., Ni@ICNPs, [9b] Ru@ICNPs, [11] Cu@ICNPs, [12] Ni@FeNi 3 [13] ). Demonstrating the potential for adaptive catalysis, multifunctional Cu@ICNPs systems proved highly active for hydrodeoxygenation [12] reactions under magnetically induced heating, showing again an immediate response to the magnetic field induced by intermittent electricity supply.…”

Nanoengineered Design of inside‐Heating Hot Nanoreactor Surrounded by Cool Environment for Selective Hydrogenations

“…In order to quantify the heating power, the specific absorption rate (SAR) was introduced to describe the amount of energy absorbed per unit of mass and was expressed in watts per gram (W g −1 ). [9,11] The hollow yolkshell nanoreactors displayed a high SAR value of ≈150 W g −1 at a m 0 H rms of 60 mT with a fixed frequency of 100 kHz (Figure S10, Supporting Information), which was mainly attributed to the good dispersibility in solution (Figure S11, Supporting Information) and the adequate saturation magnetization (Figure S12, Supporting Information) characterized by vibrating sample magnetometer.…”