Catalytic Enhancement of Inductively Heated Fe3O4 Nanoparticles by Removal of Surface Ligands

Heat management in catalysis is limited by each material's heat transfer efficiencies, resulting in energy losses despite current thermal engineering strategies. In contrast, induction heating of magnetic nanoparticles (NPs) generates heat at the surface of the catalyst where the reaction occurs, reducing waste heat via dissipation. However, the synthesis of magnetic NPs with optimal heat generation requires interfacial ligands, such as oleic acid, which act as heat sinks. Surface treatments using tetramethylammonium hydroxide (TMAOH) or pyridine are used to remove these ligands before applications in hydrophilic media. In this study, Fe3O4 NPs are surface treated to study the effect of induction heating on the catalytic oxidation of 1‐octanol. Whereas TMAOH was unsuccessful in removing oleic acid, pyridine treatment resulted in a roughly 2.5‐fold increase in heat generation and product yield. Therefore, efficient surfactant removal has profound implications in induction heating catalysis by increasing the heat transfer and available surface sites. Remove on up: The effect of ligand removal on heat transfer when a magnetic nanoparticle (NP) is activated with an alternating magnetic field using radiofrequency is investigated. Whereas tetramethylammonium hydroxide (TMAOH) treatment resulted in higher surface ligand density, acting as a heat sink, pyridine treatment reduced ligand density and improved heat transfer.