Preparation of Magnetic Tubular Nanoreactors for Highly Efficient Catalysis

We report an efficient and controllable route to prepare magnetic tubular nanoreactors composed of a mesoporous SiO 2 shell with iron‐noble metal nanoparticles inside. The key of this method is to design and fabricate Fe nanoparticles encapsulated in a mesoporous SiO 2 shell. Making use of a galvanic replacement reaction between Fe and noble metal ions, all of the noble metal nanoparticles are loaded inside the mesoporous SiO 2 shell, and thus nanoreactors are formed. Taking Pd as an example, the prepared Pd−Fe@ meso ‐SiO 2 tubular nanoreactor exhibits a high catalytic activity and excellent reusability for styrene hydrogenation under mild conditions. This study provides a facile route to fabricate magnetic nanoreactors with enhanced catalytic properties.