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With the growing number of applications for thin polymer films (e.g., corrosion-resistant coatings, photovoltaics, and optoelectronics), there is an urgent need to develop or advance cost-effective, versatile, and high-throughput manufacturing processes to produce thin polymer films and coatings with controllable properties (e.g., morphology, composition). In this work, we present a simple, cost-effective, and scalable approach: the air-assisted electrospray method for thin film coating. We systematically investigate its capabilities for producing coatings with a wide range of surface morphologies, its compatibility with three-dimensional substrates, and the fundamental understanding of the process. Through systematic control of concentration, needle configuration, and polymer selection, we demonstrate the ability to produce coating morphologies with diverse structural characteristics and excellent reproducibility. Notably, the introduction of air assistance through a coaxial needle greatly enlarges the range of achievable morphologies, particularly at lower concentrations. We also found that the position of the airflow relative to the solution is critical for determining the polymer film properties. Furthermore, we demonstrate its broad application potential in the fabrication of binderless electrodes for sodium-ion batteries. 

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.