Artificial cilia actuated by an applied magnetic field have been developed. In our previous report, we demonstrated actuated cilia of a few millimeters scale, which were fabricated by cutting a magnetic elastomer sheet. The fabricated artificial cilia worked similarly to natural cilia; however, they had a much larger structure than natural ones, and showed difficulty for use in pumping systems in micro-total analysis systems (µTAS) fields. Thus, our goal is further miniaturization. In this study, we introduce a new process of fabricating smaller pillar structures with a magnetic orientation in each pillar by ultraviolet (UV) laser machining. We also give different orientations to groups of pillars by the alternate laser machining of the mold and casting processes.

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Ferroelectric mesocrystals of Bi0.5Na0.5TiO3 (BNT) with [100]-crystal-axis orientation were successfully prepared using a topotactic structural transformation process from a layered titanate H1.07Ti1.73O4·nH2O (HTO). The formation reactions of BNT mesocrystals in HTO-Bi2O3-Na2CO3 and HTO-TiO2-Bi2O3-Na2CO3 reaction systems and their nanostructures were studied by XRD, FE-SEM, TEM, SAED, and EDS, and the reaction mechanisms were given. The BNT mesocrystals are formed by a topotactic structural transformation mechanism in the HTO-Bi2O3-Na2CO3 reaction system and by a combination mechanism of the topotactic structural transformation and epitaxial crystal growth in the HTO-TiO2-Bi2O3-Na2CO3 reaction system, respectively. The BNT mesocrystals prepared by these methods are constructed from [100]-oriented BNT nanocrystals. Furthermore, these reaction systems were successfully applied to the fabrication of [100]-oriented BNT ferroelectric ceramic materials. A BNT ceramic material with a high degree of orientation, high relative density, and small grain size was achieved.

A novel two‐step process has been developed for the preparation of Ba0.9Ca0.1TiO3 plate‐like grains with [110]‐crystal‐axis‐orientation. In the first step, plate‐like particles of a layered titanate H1.07Ti1.73O4 are solvothermally treated in a Ba(OH)2–Ca(OH)2 mixed solution, and then in the second step, heat‐treat the solvothermally treated sample to complete the formation reaction of Ba0.9Ca0.1TiO3. The formation reaction and nanostructure of the Ba0.9Ca0.1TiO3 plate‐like grains were characterized using X‐ray diffraction, FE‐SEM, TEM, and SEAD. The Ba0.9Ca0.1TiO3 plate‐like grains are constructed from spherical nanoparticles with particle size of about 10–20 nm. The spherical nanocrystals in each plate‐like grain arrange in the same crystal‐axis‐orientation direction, which presented a diffraction pattern similar to the single crystal. The Ba0.9Ca0.1TiO3 plate‐like grains were utilized to fabricate an oriented Ba0.9Ca0.1TiO3 ceramic to demonstrate the potential application of the plate‐like grains, and the [110]‐oriented Ba0.9Ca0.1TiO3 ceramic with a high degree orientation of F110 = 76% and small grain size of about 1–2 μm was obtained.

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