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A rational porous structure can efficiently enhance the electrode reaction process. In this study, we fabricated a type of three-dimensional (3D)-ordered hierarchically porous carbon via a dual-template method to support ruthenium species as efficient cathodes towards the hydrogen evolution reaction (HER). The ordered hierarchical pores comprised of three levels of porous structure, including the inverse opal-structured macroporous carbon skeleton (ca. 150 nm), the internal-ordered mesoporous structure (ca. 5 nm), and abundant microporous structure (

In this letter, high-performance TiO2/BiFeO3 heterostructure thin film is successfully prepared by introducing sol-gel derived-TiO2 (SG-TiO2) electron transport layer. A significant improvement of photovoltaic performance has been achieved. 3.674% power conversion efficiency of the thin film is obtained with open-circuit voltage (Voc) of 1.64 V, short-circuit photocurrent (Jsc) of 3.5 mA/cm2 and fill factor (FF) of 64%, which implies that the introduction of a TiO2 would improve the photovoltaic performance under visible light illumination. Our work demonstrates that the TiO2/BFO heterostructure thin film possesses the potential for better use in the solar energy devices applications.

The Bi1 + xFe0.95Cr0.05O3 (BFCO) (x = 0, 5, 10, 15 and 20%) thin films are fabricated on FTO/glass substrate using a chemical solution deposition method and sequential-layer annealing process. The effects of the excess Bi content on crystalline structure, morphology, and electrical performance of BFCO thin films are investigated. All the BFCO thin films are crystallized into polycrystalline perovskite structure and belonging to the space group of R3c. The BFCO thin films with 5 and 10% excess Bi contents possess no impurity phase. Especially, a dense surface morphology and columnar crystal structure can be obtained for the film with 5% excess Bi content. Especially, the one possesses superior ferroelectricity with a relative high remnant polarization (P r) of 69.8 µC/cm2 and low coercive electric field (E c) of 291 kV/cm at 1 kHz due to the relatively low leakage current density of 3.04 × 10− 5 A/cm2 at 200 kV/cm.

0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 (0.65PMN-0.35PT) thin films were deposited on Pt/Ti/SiO2/Si substrates annealed from 550 to 700 °C using sol-gel process. The effects of annealing temperature on microstructure, insulating, ferroelectric and dielectric properties were characterized. The result reveals that 0.65PMN-0.35PT thin films possess a polycrystalline structure, matching well with the perovskite phase despite the existence of a slight pyrochlore phase. The film samples annealed at all temperatures exhibit relatively dense surfaces without any large voids and the grain size increases generally with the increase of the annealing temperature. Meanwhile, pyrochlore phase is considerably generated because of the deformation of perovskite phase caused by volatilization of Pb at an excessive high-temperature. The film annealed at 650 °C exhibits superior ferroelectricity with a remanent polarization (Pr) value of 13.31 μC/cm2, dielectric constant (er) of 1692 and relatively low dielectric loss (tanδ) of 0.122 at 104 Hz due to the relatively homogeneous large grain size of 130 nm and low leakage current of approximately 10-6 A/cm2.

Bi2Fe4O9 (BFO) is one of the most important photocatalyst materials and its composition with graphene may leave an optimizing effect on the photocatalytic performance. In this paper, reduced graphene oxide (RGO) with various contents is selected to be composited with BFO successfully via one-step hydrothermal method. A series of BFO-xRGO (x=0, 1.25, 2.50, 3.75, 5, 6.25, and 7.50 wt.%) were prepared and the effects of RGO content on crystalline, light absorption, impedance, and photocatalytic degradation rate of methyl violet (MV) solution are characterized. The entire film samples exhibit enhanced photocatalytic efficiency. Especially, with 5 wt.% RGO content added, the film sample shows the best photocatalytic degradation efficiency with a MV solution degradation rate of 95%. This implies that the composition of RGO allows BFO-based thin film as an efficient photocatalyst candidate, and as well, the BFO/RGO composite possesses the potential for better use in the related photocatalyst applications.

In this paper, octadecyltrichlorosilane (OTS) self-assembled multilayer (SAM) films are fabricated on Pyrex glass by dipping method. The hydrophobicity, constituent and surface morphology of OTS SAM at various dipping times in solutions of 1, 2 and 5[Formula: see text]mM concentrations are investigated. Characteristic absorption peaks around 2850 and 2920[Formula: see text]cm[Formula: see text] are observed by FTIR and island-like structures on samples are detected by AFM. After 15[Formula: see text]min dipping time for solution of 5[Formula: see text]mM, water contact angle of the sample reaches the maximum value of 116.4[Formula: see text] with relatively low surface root mean square (Rms) roughness of 0.152[Formula: see text]nm. The critical surface tension ([Formula: see text] of the analyzed sample is 18.2[Formula: see text]dyne/cm. The optimum dipping time in the solution of 5[Formula: see text]mM for a complete SAM film is about 30[Formula: see text]min. The study of the optimal conditions for the formation of integrated OTS SAM has significant scientific and practical values in modification of solid surfaces.