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Magnetized soft ferromagnetic films with micrometer thickness were studied. A FeSi film, with a total thickness of 2000 nm, separated by 10 nm-thick Ta interlayers, was fabricated using the direct-current magnetron sputtering technique. The thickness of each FeSi layer between adjacent Ta layers was 100 nm. Hysteresis loop measurement was used to characterize the magnetic properties of the layer. X-ray diffraction patterns and high-resolution transmission electron microscopy were used to characterize its texture. The experimental results showed that the FeSi film separated by Ta interlayers exhibited a lower saturation magnetization and a higher coercivity than those of the 1140 nm-thick FeSi film. The insertion of Ta interlayers resulted in the disappearance of the crystal plane of FeSi (221), and better texture of the crystal plane of FeSi (210). The FeSi film exhibited a crystal plane of FeSi (210) with a bcc crystalline structure. The Ta interlayers were partially amorphous, exhibiting crystal plane of Ta (002) and TaSi2 (310). The matching of magnetic properties between interlayers and soft magnetic layers played an important role in maintaining its soft magnetic properties. [ABSTRACT FROM AUTHOR]

Abstract: To gain in‐depth insights into the relevant exposed crystal planes for the photocatalytic performance of perovskite‐structured oxides, SrSnO3 nanocrystals with different microstructures were synthesized and their photocatalytic activity for the degradation of simulated dye was investigated. The as‐obtained orthorhombic SrSnO3 nanorods with exposed {001} crystal planes showed higher photocatalytic activity for decomposing methylene blue than that of SrSnO3 nanoribbons with exposed {111} crystal planes. The surface atomic configurations revealed that the quantity of SnO2 overlayer on the {001} crystal facets is slightly greater than that on {111} crystal planes, which results in exposed {001} crystal facets of the SrSnO3 nanorods that can exhibit better activity in the photocatalytic process, due to fewer lattice defects, which act as traps for photogenerated charge carriers to decrease the recombination of photoexcited electrons and holes. This originated from narrowing of the crystal face distance and slight variation of the unit cell parameters; the crystallographic axis became shorter and the value of lattice strain became smaller. As a result, SrSnO3 nanocrystals exhibited different surface behavior under post‐treatment conditions and exhibited variation in the photocatalytic properties. The findings reported herein highlight the importance of probing the properties of surface facets in the evaluation of the photocatalytic performance of ternary metal oxides. [ABSTRACT FROM AUTHOR]

NaNb x Ta 1-x O 3 , sodium tantalate and niobate with B atoms substitution is synthesized by a facile one-step hydrothermal method. They are effective photocatalysts for hydrogen evolution from water splitting without co-catalyst. NaNb 0.33 Ta 0.67 O 3 exhibits the best performance with produced H 2 of 1038 μmol g−1 in 5 h, which is more than 5 times than NaTaO 3 and NaNbO 3. It is also close to 5 times and 2 times than NaTaO 3 /Pt and NaNbO 3 /Pt, respectively. NaNb 0.33 Ta 0.67 O 3 has a transition state crystal structure between NaTaO 3 and NaNbO 3 crystalline phase. Moreover, XPS, ESR and TEM characterizations demonstrates that there are abundant oxygen vacancies in NaNb 0.33 Ta 0.67 O 3. These features give the catalyst excellent properties, such as good light harvesting and efficient charge separation confirmed by optical and electrochemical characterizations. This work may offer a strategy to develop perovskite sodium tantalate and niobate with controllable crystal structure and oxygen vacancies for highly efficient photocatalytic hydrogen evolution in the absence of co-catalyst. [Display omitted] • NaNb x Ta 1-x O 3 photocatalysts were prepared by a facile hydrothermal method. • NaNb x Ta 1-x O 3 had superior photocatalytic H 2 evolution ability without co-catalyst. • The maximum yield of H 2 was 1038 μmol. g−1 over NaNb 0.33 Ta 0.67 O 3 in 5 h. • Produced H 2 over NaNb 0.33 Ta 0.67 O 3 was more than 5 times than NaTaO 3 and NaNbO 3. • Excellent performance depended on transition state structure and oxygen vacancy. [ABSTRACT FROM AUTHOR]