Magnetically Induced Orientation of Mesochannels in Mesoporous Silica Films at 30 Tesla

We demonstrate the magnetically induced orientation of mesochannels in mesoporous silica films prepared with low‐molecular‐weight surfactants under an extremely high magnetic field of 30 T. This process is principally applicable to any type of surfactant that has magnetic anisotropy because such a high magnetic field provides sufficient magnetic energy for smooth magnetic orientation. Hexadecyltrimethylammonium bromide (CTAB) and polyoxyethylene‐10‐cetyl ether (Brij 56) were used as cationic and nonionic surfactants, respectively. According to XRD and cross‐sectional TEM, mesochannels aligned perpendicular to the substrates were observed in films prepared with low‐molecular‐weight surfactants, although the effect was incomplete. The evolution of these types of films should lead to future applications such as highly sensitive chemical sensors and selective separation. Channels of the perpendicular style: Continuous and transparent mesoporous silica films with perpendicular mesochannels can be prepared by applying an extremely high magnetic field of 30 T generated by a hybrid magnet. This process is principally applicable to any type of surfactant with magnetic anisotropy.