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Ordered ZnO arrays with a peculiar nanostructure were synthesized by a multistep synthesis process. The first step was the preparation of ZnO seed to induce the formation of ZnO array via potentiostatic electrodeposition method using a typical three electrode set-up. The second step was fabricating ZnO array along seed by Chemical Bath Deposition. Structural analysis of ZnO was carried out with X-ray diffraction (XRD), which showed a hexagonal wurtzite structure, and the selected area electron diffraction (SAED) patterns indicated that nanocrystalline is a part of monocrystal. The scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to study the microstructure, and showed a pagoda-like microstructure with a tiny top and large bottom, which had an average top diameter of exceeding 800nm at seed-depositing time of 60s, and then growth mechanisms are subsequently given a further explanation, viewed from kinetics and thermodynamics. In addition, the current-voltage curves of schottky diode devices with ZnO nanopagoda arrays revealed that ZnO films arrays along grown ZnO seed had a higher reverse saturation current than ZnO films grown without seed, which are A and A, respectively. The minimum turn-on voltage of the diode with ZnO seed deposited 60s is 0.18V, without seed is 0.52V. A peculiar nanostructure which is similar to hexagonal pagoda with a tiny top and large bottom was observed via seed-induced method. However, semi-ZnO/metal-Al Schottky diodes were assemble, and that structure exhibits a typical rectifying behavior, and obtained low turn-on voltages which represent current responses, 0.52 V, 0.40 V, 0.18 V, respectively. The as-grown ZnO nanopagoda along grown ZnO seed with the deposition time of 60 s exhibited a slightly higher reverse saturation current than the as-grown ZnO arrays without ZnO seed. [ABSTRACT FROM AUTHOR]

In this paper, the Ba (1 − x) Sr x TiO3 (BST) fiber arrays in an orderly manner were successfully fabricated by electrospinning. The arrangement of the fiber arrays and their dielectric properties at different rotation speeds were investigated. The microstructure, phase composition and dielectric properties of the fabricated fiber arrays were detected via field-emission scanning electron microscope, X-ray diffraction and automatic component analyzer. The results indicated that the orientation of the BST fiber arrays could be affected by the drum rotational speed variation of the roller receiver. The orientation degree of the BST fiber arrays increased and the diameter of the BST fiber arrays decreased with the increasing of the drum rotational speed. With the content of polyvinylpyrrolidone at 8% and the speed of 1000 r/min, the orientation degree of the BST fiber arrays gets a better state and the best dielectric constant of 104. Moreover, the ferroelectric performance of BST fiber arrays in ambient and cryogenic environments has a maxima Curie temperature of − 5 ∘ C. [ABSTRACT FROM AUTHOR]