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Rapid formation of active, mesoporous, and crystalline TiO2 photocatalysts via a novel microwave hydrothermal process is presented. Crystalline anatase mesoporous nanopowders 100–300 nm in size with worm hole‐like pore sizes of 3–5 nm were prepared by a modified sol–gel of titanium tetra‐isopropoxide, accelerated by a microwave hydrothermal process. The organic surfactant, tetradecylamine, which is used as a self‐assembly micelle in the sol–gel and microwave hydrothermal process, enables to harvest crystallized mesoporous anatase nanoparticles with a high‐surface area. Mesoporous worm hole‐like and crystalline powders with surface areas of 243–622 m2/g are obtained. X‐ray diffraction, N2‐adsorption isotherms (Barrett–Joyner–Halenda and Brunauer–Emmet–Teller method), scanning electron microscope, and transmission electron microscope are used to identify the characteristics and morphologies of the powders. It is shown that crystallization by calcination at 400°C/3 h inevitably reduced the surface area, while the microwave hydrothermal process demonstrated a rapid formation of crystalline mesoporous TiO2 nanopowders with a high‐surface area and excellent photocatalytic effects.

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Template growth of Fe 3 O 4 nanowire arrays via precipitation and subsequent microwave hydrothermal process was investigated. Anodic aluminum oxide and polycarbonate templates were immersed in a ferrous chloride and ferric chloride mixture and the precipitation of Fe 3 O 4 took placed by adjusting the solution to pH49. A microwave hydrothermal process was subsequently performed at 1501C for 30 min in order to further enhance the crystallinity of the Fe 3 O 4 nanowires. The length of the nanowires is about 5-20 mm and the diameter is about 220 nm, with perfect surface finishing. The nanowires were polycrystalline cubic spinel structures and composed of nanometer-sized particles, as characterized by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. Magnetic properties in parallel and perpendicular direction were measured using a vibrating sample magnetometer, where the magnetization in the perpendicular direction of the nanowires is higher than that of the parallel direction. Microwave hydrothermal treatment improved the crystallinity and morphology of Fe 3 O 4 nanowires and resulted in a much better magnetization than that without microwave hydrothermal treatment.

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