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Surface defects were introduced into La 2 TiO 5 nanoparticles, which possessed the following obvious advantages: (1) improving the absorption capacity of visible light and broadening the spectral response range; (2) the formation of defect energy levels is conducive to the transition of electrons; (3) oxygen vacancy can further improve the photocatalytic activity. The yield of photocatalytic nitrogen fixation under simulated sunlight could reach 158.13 μmol·g−1·h−1 and the photocatalytic mechanism was systematically studied. [Display omitted] • Defective La 2 TiO 5 nanpparticles with broad visible light absorption were obtained. • Without any precious metal co-catalyst, the NH 3 yield of photocatalyst under simulated sunlight irradiation was 158.13 μmol·g−1·h−1. Highly active and efficient photocatalysts are crucial for the exploration of ammonia synthesis because of the serious problem of energy deficiency. La 2 TiO 5 (LTO) perovskite materials have great advantages in the field of photocatalytic nitrogen fixation because of the broadly diversified properties. The rational design of surface defect is a valid method to modulate photoinduced charge traps and create defect energy levels, especially it is an effective way to suppress the photoinduced charge recombination. Herein, LTO was obtained by a simple sol-gel method and was further reduced by NaBH 4 to introduce oxygen defect on its surface. UV–vis spectra proved that the surface defects could reduce the band gap value of samples, which is beneficial for improving photocatalytic nitrogen fixation activity. For the best photocatalytic samples with good cycle stability, the nitrogen fixation rate is 158.13 μmol·g−1·h−1. The mechanism of photocatalytic nitrogen fixation was proposed by the PL, XPS, and PEC results, which provided possibilities for exploring more promising perovskite catalysts in the field of nitrogen fixation. [ABSTRACT FROM AUTHOR]

In this work, a novel quaternary heterostructured Ag–Bi 2 O 2 CO 3 /Bi 3.64 Mo 0.36 O 6.55 /Bi 2 MoO 6 composite was fabricated through a low-temperature solution-phase route. The XRD, SEM, EDX and XPS results indicated the as-prepared sample is a four-phase composite of Bi 2 O 2 CO 3 , Bi 3.64 Mo 0.36 O 6.55 , Bi 2 MoO 6 , and Ag. The photocatalytic activities of the as-synthesized samples were evaluated towards the degradation of phenol red aqueous solution. The results showed that the as-synthesized Ag–Bi 2 O 2 CO 3 /Bi 3.64 Mo 0.36 O 6.55 /Bi 2 MoO 6 photocatalysts displayed much higher photocatalytic activities in comparison with pure Bi 3.64 Mo 0.36 O 6.55 , pure Bi 2 MoO 6 , and Bi 3.64 Mo 0.36 O 6.55 /Bi 2 MoO 6 composite. Among them, the 2.5% Ag–Bi 2 O 2 CO 3 /Bi 3.64 Mo 0.36 O 6.55 /Bi 2 MoO 6 sample performed the best. The enhanced photocatalytic activity of the composite photocatalyst was attributed predominantly to the efficient separation of photoinduced electrons and holes. In addition, Ag nanoparticles were photodeposited on the surface of the composite to increase visible-light absorption via the surface plasmon resonance, which is also beneficial to the enhancement of photocatalytic performance. The possible photocatalytic mechanism of the quaternary heterostructure was also discussed in detail. [ABSTRACT FROM AUTHOR]

The ZnO nanorods/ZnSe nanosheets heterostructure had been successfully fabricated by the spin coating method. The evolution of the structural, optical and photocatalytic properties of the samples with different spin coating times was comprehensively investigated. The X-ray diffraction (XRD) patterns showed that the relative intensities of ZnSe peaks increased gradually with the increase of spin coating times, but the ZnO peaks were relatively suppressed, which had a good agreement with the results of Raman spectra. The scanning electron microscope (SEM) and transmission electron micrograph (TEM) images further confirmed that the ZnSe nanosheets (NSs) had been successfully assembled on the top surfaces of the ZnO nanorods (NRs) and in the upper parts of the gaps between the rods. At room temperature, the ZnO/ZnSe heterostructures exhibited a relatively suppressed UV emission together with a dramatically enhanced deep-level emission. In addition, the heterostructures exhibited remarkable photocatalytic activities. The type-II staggered band alignment and defects formed at the ZnO/ZnSe interfaces should be the key factors for improved photocatalytic performance, and the probable photocatalytic mechanism was discussed in detail. [ABSTRACT FROM AUTHOR]

Abstract: The Fe x Pt100−x nanoparticles (NPs) with different nominal atomic rations (30≤x≤80) were synthesized at 700°C by the sol–gel method. The structure, morphology and magnetic properties of the samples were investigated. When the Fe content in the Fe–Pt alloy NPs was 30at%, FePt3 NPs were successfully synthesized. With the increase in Fe content up to 50at%, it was found that the superlattice reflections (001) and (110) appeared, which indicated the formation of the L10-FePt phase. Meanwhile, the FePt3 fraction was reduced. When the Fe content increased to 60at%, single-phase L10-FePt NPs were synthesized. The coercivity (Hc), saturation magnetization (Ms) and chemical order parameter S for Fe60Pt40 NPs were as high as 10,200Oe, 17.567emu/g and 0.928, respectively. With the further increase of the Fe content to 80at%, only Fe3Pt phase existed and the Hc of the Fe3Pt NPs decreased drastically to 360Oe. [Copyright &y& Elsevier]