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A series of Ni1-xCux/Sm-doped ceria (Ni1-xCux/SDC) anodes have been prepared through introducing a soluble pore former with the co-pressing and co-sintering process. Uniform hierarchical porous microstructures are formed in Ni0.9Cu0.1/SDC anode with interconnected large pores of 2–5 μm and 100–300 nm small pores on the wall. The solid oxide fuel cell (SOFC) based on such anode exhibits exceptional electrochemical catalytic activity for dry CH4 oxidation and a maximum power density of 379 mW cm−2 is acquired at 600 °C. Durability test results show only 2.4% power density drop is observed after 72 h operation under a constant cell voltage of 0.5 V. The results have demonstrated that the optimization of anode microstructures is an effective way to improve the performance and long-term stability of Ni1-xCux alloy-based anode-supported SOFC.

The (1 0 0) oriented (Pb,Sr)TiO3 (PST) thin films were prepared using terbium-doped lead titanate as inducing layer. Misfit strain of the PST thin films changed gradually along direction of thickness and with different compositions. Controlled by the strain, the Curie temperature was independent of the composition of the PST and the width of the Curie peak was broadened. The as-prepared PST thin films exhibited stable high dielectric tunability which was almost independent of composition as well as applied temperature. With the composition of PST changing from PST35 (PbxSr1−xTiO3 x = 0.35) to PST50, the room temperature tunability of the PST thin films maintains a stable value of about 40%. At a high applied temperature of 200 °C, the PST thin films still show a high tunability of about 35%. The strain-assisted control of the Curie temperature and the Curie peak width is attractive in designing high stable devices with high dielectric tunability.

In order to inhibit carbon deposition in Ni/Sm-doped ceria (SDC) anode in a solid oxide fuel cell, copper was incorporated through both addition of preformed Ni 0.95 Cu 0.05 alloy and impregnation of Cu nitrate solution. It was found that besides those preformed Ni-based alloy grains, some Cu, which is actually Cu-rich alloy, attached preferentially on the surface of those Ni-based alloy grains as nanoparticles. Carbon deposition in such anode decreased significantly with the increasing amount of Cu-rich alloy nanoparticles. For anode with 10 wt.% Cu impregnation and 600 °C reduction, the carbon deposition was only 12.7 wt.% when exposed to dry methane for 2 h. In comparison, that was actually less than 1/10 of Ni 0.95 Cu 0.05 /SDC anode without any Cu impregnation. It is demonstrated that the existence of Cu rich alloy nanoparticles in Ni 0.95 Cu 0.05 /SDC anode could mitigate carbon deposition owing to the suppression of carbon nucleation and decrease of growth site.

Titanium silicide thin films and nanowires (NWs) were prepared on a glass substrate using the APCVD method. Gaseous SiH 4 and TiCl 4 were used as precursors for Si and Ti, respectively. TiSi 2 thin films were precipitated on the glass substrate first, and then single-crystal TiSi NWs were grown on the TiSi 2 thin films as-prepared by controlling the concentrations of the source gases, SiH 4 and TiCl 4 , without using any catalysts. The TiSi NWs were typically 1–2 μm long and 15–50 nm thick. The growth direction of the NWs was perpendicular to the (1 1 0) plane, in which a competition in growth rate among different crystallographic planes of the TiSi crystalline phase occurs. The oriented growth of the TiSi crystalline phases is responsible for the formation of the NWs.

In this work, a phase-separation-induced self-assembly (PSIA) approach was developed to prepare PbTiO 3 nanodots on substrates. Lead titanate nanodots on Si wafer were obtained through Marangoni instability induced phase separation and following heat-treatment. It was found that acetylacetone added in the precursor played important roles not only in the incorporation of Pb into the nanodots, but also in the phase separation process. The size and density of PT nanodots could be controlled through the concentrations of precursor and phase separation adjuster, i.e., tetrabutyl-titanate and polyvinylpyrrolidone. The nanodots size and density were from 10 nm to ∼100 nm and from 0.5 × 10 10 dots/cm −2 to 4.6 × 10 10 dots/cm −2 respectively. Such preparation provides a simple way to prepare titanate nanodots on substrate.

α-tricalcium phosphate (α-TCP), biphasic α/β-tricalcium phosphate (α/β-TCP) with different two phase ratio and β-tricalcium phosphate (β-TCP) powders were prepared by calcining an amorphous calcium phosphate (ACP) precursor at a temperature ranging from 800 to 900 °C. The microstructural characterization revealed that the particles in the monophasic and the biphasic TCP powders had about 1 μm in size, and agglomerated by 500 nm ones. In comparison with monophasic TCP powders, the dissolution–reprecipitation behaviors of the biphasic TCP powders in an acetate buffer solution with pH 5 were studied. The biphasic TCPs demonstrated a different behavior from the monophasic TCPs, including changes in morphology and crystalline phase. The unique behavior can be tailored by controlling the α-TCP content in the biphasic TCP powders.

Ferroelectric/ferrimagnetic PbTiO 3 /NiFe 2 O 4 composite thin films with nano-scale PbTiO 3 and NiFe 2 O 4 phases homogeneously dispersed in each other were synthesized by sol–gel in situ method. The phase structure and morphology of the composite thin films and their dielectric, ferroelectric and ferromagnetic properties were measured respectively in detail. Results show that the ferroelectric/ferrimagnetic composite thin film with PbTiO 3 and NiFe 2 O 4 phases is successfully synthesized at heat-treatment temperature of 850 °C. It is significantly isotropic due to the nanometer scale grain size of the constituent PbTiO 3 and NiFe 2 O 4 phases. A capacitance of 60–100 pF with a good frequency independence over the conventional applied frequency range, ferroelectric hysteresis loops with the applied electric field of 500 kV/cm, a saturation magnetization higher than 4.8 MT, and a coercive field of 5280 A/m with well suitable ferrimagnetic properties are obtained from the thin film with the composition ratio PbTiO 3 /NiFe 2 O 4 of 50/50 post heat-treated at 850 °C. The ferroelectric/ferrimagnetic composite thin film is desirable for multifunctional device application.

ZnO nanoflowers were grown on Si substrate through the adoption of a ZnO seed-layer with unique morphology and subsequent immersing in suitable growth medium. Depending on the ZnO seed-layers, ZnO nanostructures varied from nanosheets to nanoflowers. The ZnO nanoflower is composed of nanosheets with 20–30 nm in thickness. XRD results revealed a hexagonal phase of these nanostructures. The ZnO nanoflowers can exhibit strong UV and relatively weak visible luminescence at room temperature. The water wettability of the ZnO nanoflowers showed good hydrophilic property without UV illumination.

Well-defined crystalline dendritic structured lead selenide (PbSe) was prepared via a template-free, facile hydrothermal route using Pb(NO 3 ) 2 as the lead ion source, selenourea (CH 4 N 2 Se) as the selenide source at 150 °C for 24 h. The sample was characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electronic microscopy (TEM). XRD patterns showed that phase-pure PbSe was produced. Novel PbSe dendritic structure is synthesized as indicated by SEM and TEM. The quality and composition of the products was determined with X-ray photoelectron spectroscopy (XPS). The influencing factors for the morphologies are discussed and the formation mechanisms are proposed. The studies on the corresponding photoluminescence (PL) properties of the dendritic structured PbSe were also carried out.

Pure single-phase Co-doped (Na 0.5 Bi 0.5 )TiO 3 crystallites have been successfully synthesized by a simple hydrothermal method. The as-prepared powders were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), physical property measurement system (PPMS), and electrostatic force microscopy (EFM). It is suggested that the as-obtained Co-doped (Na 0.5 Bi 0.5 )TiO 3 crystallites exhibited a weak ferromagnetic order at room temperature and also possessed ferroelectric property in response to the applied external electric field. This method may provide an available way to get single-phase multiferroics and to resolve the problem of the scarcity of single-phase multiferroics in nature.